I have nearly completed working on my game Golden Fall 2 for Steam.

https://store.steampowered.com/app/1292410/Golden_Fall_2/​

How do I prepare for release?

I tried to collect as many wish lists as I could. I got about 180.

I have a Demo, which I think helps.

I am also going to attend a Steam Festival later on.

A few questions:

1. Do I need to get reviewers to review my game? Or unless it picked by a really big reviewer(almost 0 chance) it's better to not get reviews at all?
2. Do I need to put (more)ads? I tried to put Google Search ads, but not sure of their effectiveness. Sometimes I get more wishlist, sometime I don't. I can't tell exactly what is the link.
3. What initial sale discount? Steam suggest doing that with new Released.
4. Should I Release before the Festival? During? Or After? As the Festival will bring some exposure.

All of those are complex questions that have to do with your business plan.

#1, getting reviewers to review it: hopefully you've had LOTS of people already play and review your game, and you've iterated on that feedback already. As part of releasing a major project it is important to have many reviews, have them be positive, and have them show up prominently. The way to ensure that happens is with truckloads of cash. Your business plan should include all of this, details of how you iterate, how you manage your releases (which absolutely must be plural if you're planning to succeed), and how reviewers fit into your broad marketing plan. Assuming this is a minor hobby product and not a major commercial venture, you cannot ensure those things, so you'll need to iterate and expand on a path that is unique to you and your product.

#2, putting out more ads: advertising effectively is a hard thing. Generic search ads are not targeted and are probably mostly a waste, but may increase your sales. Most people require multiple exposures before they're interested enough to consider it, and more exposures still before they're willing to buy. Exactly how you reach those potential customers depends on far more factors than fit a forum posts, and in fact, libraries are filled with books about it, and journals are filled with academic research. It is not an easy thing.

#3, initial discount: This fits closely with #2. Why do you price the way you do? Your pricing strategy is closely tied to your marketing strategy. Again, there is a tremendous body of research on the subject,

#4, release before the Steam Festival: What does your marketing plan say? The festival certainly can provide a great way to get feedback, but hopefully you've had enough small releases on your own to work out the game kinks, iterate on your product, and are ready to show a product that is several versions in and not just a prototype. The festival has hype around it, but you're also automatically competing with everyone else who is there, so hopefully your marketing plan already accounts for that.

“Build it and they will come” is not a reliable marketing strategy, but it is sadly common.

For something more reliable: You should have done all your market research, identified market opportunities that could be profitable, and built a game that both inspires you and also reaches those market opportunities. You should then develop the game systematically with feedback and marketing, iterating repeatedly, updating the design and the implementation after feedback, then repeating the loop. Designers, other game developers, friends and families, their expanded networks, all of these should have been hit exhaustively. If you have the ability to hire testers, they should also be pressed heavily for feedback and iteration. Only after that should it be expanded to reviewers, public betas, and pre-launch sales.

With all the explanation out of the way, answers you probably don't want:

1. No. No.
2. Yes. Correct observations. It isn't easy. Marketers probably could.
3. As your research guides, if any. Commonly yes, but not required and sometimes its harmful, even fatal to the business.
4. Yes. Yes. Yes. True for better and for worse.