Online Card-based Character Building/ Battle Game.

I'm brainstorming ideas for a game where players build up a character, graphically represented by a traiding card containing a picture and the character stats. The basic idea is that players join a lobby and from there join either one on one battles, or based team variations.

Definitely not a "trading card", only an advanced summary of character information. Are you sure that an enormous number of player character portraits are more useful than improving in-game graphics?

The idea is to have leveling broken down into two stats, similar to games like Black Ops. You have experience, which dictates your level (which in turn dictates your abilities) and you have credits/points, earned through victories and participation in-dame - these will dictate what items your character can purchase.

It is a multiplayer game: do you allow players to give money to other players? What can they buy? I can easily imagine player gangs that pool all their money to outfit one of them with unreasonably good and expensive equipment and exploit it.

As you level/change/decorate your character, the trading card image and stats will update accordingly.

The backbone of this idea is to appeal to people's desire to customise and show off things, further to this, the "tech. tree" of character evolution /new items/ character appearance should start with a fairly uniform choice of default base characters who can be individualised heavily. To this end, the tech. tree should be very diverse, and also, radiate outwards from the central default charachters with multiple choices - instead of being a linear path that everyone follows in the same way. The reason for this, is that the higher the level of two characters, the more diverse they are likely to be.

Character appearance is unimportant, unless your target audience has an interest in dress-up dolls, while both items and character evolution are subject to saturation.
All high level characters are going to converge to the same optimal "build" (at most, one of a few if there are major mutually exclusive character development choices like big and strong vs small and stealthy). More options are going to be simply ignored, or to add another advancement step to the same optimal schedule. At best, you can add a layer of customization that is so unimportant that the choice is arbitrary.
All rich characters are going to converge, even more unavoidably, to the best available gear for a given purpose. Customization would consist of useless trophies, of acquiring A before B instead of B before A on the way to an A+B set, and of artificial variations of the same equipment with no real difference.

Now I am working on the way the actual combat could take place. I would like it to be turn based, but beyond that I am open to suggestions.

Study existing games. By the way, do you already have any definite influence?

The setting is a futuristic fantasy, so I can include the lores of both witchcraft/wizardy and sci-fi technology. I would also like to give players the option of following fictitious religions/ faiths as their characters grow. These could all be taken into account, when thinking of categories for attack/defence/other miscellaneous moves and gestures.

Religion affecting combat?

I want the battling to support the diversity of the character building, allowing players to really put their own stamp on the gameplay.

You seem to be designing this backwards: you should invent a basic combat system first, ensure there are many different reasonable things to do in combat and balance them against each other, and finally figure out which items and character features are needed to perform them; they are going to become the many valid character building options you need for diversity.
As you add combat complications, they'll add further tactical depth and more character building opportunities.

Definitely not a "trading card", only an advanced summary of character information. Are you sure that an enormous number of player character portraits are more useful than improving in-game graphics?

I chose the term; "trading card" to illustrate the nature of how the stats are displayed, however, I always imagined that the game could produce jpegs of the players' cards, intended for use in things like their forum signatures (just an example). While the cards wouldn't be traded as such, they would be essentially able to be shared over the web, and realistically, could be exchanged. I opted to display the character graphics in this way, because the game if developed, will be an indie one, presumably with the trappings of independent game development. I would like to handle the graphic design, prefer to work in 2D, and because of the intended size of the tech. tree, producing at-least-8-frame animated sprites and paper-dolls for each item would be too time consuming.

It is a multiplayer game: do you allow players to give money to other players? What can they buy? I can easily imagine player gangs that pool all their money to outfit one of them with unreasonably good and expensive equipment and exploit it.

Not really. As I said in my original post, the game's currency system will be similar to the Black Ops currency system. Players do not buy and sell items to each other, they buy from a store which, to them, makes items/ spells/ clothing/ weaponry available on a level/ having enough currecy basis. Each player's level and arsenal is their own responsibility, so there would be no "pooling".

Character appearance is unimportant, unless your target audience has an interest in dress-up dolls, while both items and character evolution are subject to saturation.
All high level characters are going to converge to the same optimal "build" (at most, one of a few if there are major mutually exclusive character development choices like big and strong vs small and stealthy). More options are going to be simply ignored, or to add another advancement step to the same optimal schedule. At best, you can add a layer of customization that is so unimportant that the choice is arbitrary.
All rich characters are going to converge, even more unavoidably, to the best available gear for a given purpose. Customization would consist of useless trophies, of acquiring A before B instead of B before A on the way to an A+B set, and of artificial variations of the same equipment with no real difference.

Firstly, that's a fairly broad remark - character appearance is not unimportant. Why else would so many games include character attire customisation options and other visual tweaking tools? Secondly, wording it like "A target audience with an interest in dress-up dolls" is one way of putting it. I am not creating any illusions about the fact that this is exactly the target audience - people who want to customise their characters - "dress-up dolls" makes it sound like a game intended for Barbie fanatics, which is frankly misleading. The whole point of the tech. tree being the way I described is that there is no optimum, simply a balanced choice of several, equally beneficial outcomes. The tech. tree will be made up of many paths (again, balanced). Someone who takes path 1, and progresses to a high level will only be able to access the high level options whithin path 1 and so on. If they wish, they will be able to start from square one and access the path 2 unlockables, but in the time this takes could have doubled their path 1 level.

Study existing games. By the way, do you already have any definite influence?

The design is influenced by a wide variety of games, naturally, all of the games I have ever played are likely to have had some conscious or unconscious impact to some degree or another. Notable games include simple graphical style influences, like the massive array of sprite based isometric RPGs (both independent and mainstream) on the market to date, namely the use of paper-doll graphic arangement. Secondly, the gameplay dynamics of several tabletop games like the Warhammer series are having an influence on my ideas. A great deal of the gameplay in these examples is based on statistic cards which show what units can and can't do, and how they react to different scenarios.

Religion affecting combat?

Yes. This could be easily written in, in a variety of different ways - and has been in many other games. One off-the-top-of-my-head for instance would be: "A player has a high level of faith, this influences his statistical likeliness that attacks will work etc..." (This faith level could be raised by wearing certain amulets or whatever, the effect of which, could in simple terms be referred to as luck).

You seem to be designing this backwards: you should invent a basic combat system first, ensure there are many different reasonable things to do in combat and balance them against each other, and finally figure out which items and character features are needed to perform them; they are going to become the many valid character building options you need for diversity.
As you add combat complications, they'll add further tactical depth and more character building opportunities.

It's not really that I'm designing the game backwards, the idea of a character evolving game based on a radial tech. tree simply came to me as a notion first. I decided to persue it, to which end, I made my original post asking how to go about developing an endearing combat system so that the game could be done justice. I am trying to invent a basic combat system first, which is why I now refer to my original statement:

Any ideas anyone wants to throw into this are extremely welcome.