Dark souls was built around a dark world-setting. The game really only followed one rule: be true to the setting.
Difficulty naturally came about from following this rule. The setting was gruesome, cold and cruel. The game had to be the same. Customisation only went as far as the natural differences between people and races.
I know I'm diverging from writing here, but from your survey, I feel you currently have fundamental flaws. Anything that takes from the setting is a flaw in a dark souls-esque game. You want your player enthralled into your world, not to bring them out of it. Minigames would just be a gimmick. The main objective shouldn't be either of the ones you mentioned. You shouldn't start with a powerful weapon simply because it lacks progress for the player. You can start with a weapon that can grow stronger as your character does, but never start at a high point. Your player wants to reach that point through their own effort.
To move onto your story, there isn't much there. There is nothing wrong with it, but there isn't anything great about it either. It's more of a starting point for you to begin writing from.
As for mechanics, the fighting style won't separate you from other games. Don't try and change that too much. Try and perfect it for sure, because dark souls fighting style had many flaws. But to do that, you have to decide on what direction you want to take it. Do you want it to be fast and fluid? Or slow and careful. Or somewhere in the middle. It's better if you choose only one direction for the fighting style, otherwise it'll be too much work.
I also recommend balancing it around either melee or ranged weapons. Have you played Salt and Sanctuary? Great game, but using the bow literally breaks the game, and the gun is too overpowered. They wasted development time on something that adds no value to the game. And the game has too many flaws for them to justify that.
Keep the monsters and bosses fair. Every attack they do must be able to be countered. If a player ever feels that they can only beat an enemy or boss through luck, rather then their own skill, then you have failed.
Finally, the places in your gameplay where you can make a difference is the weapons, magical abilities and progression system. Though dark souls method for all of these are tried and true, it doesn't mean you have to follow it. Innovation may lead to failure or success, but that's ultimately up to you.
