These are often in the database as well. Indie games also have a very good chance of working without any changes in Proton, IME. They usually aren't very "high tech" and I suspect that at least some of their creators test them with Proton.

If they are built on Godot, Unity, Unreal, or are built with SDL+OpenGL or SDL+DirectX or C# MonoGame any kind of combination that is reasonably common in the last 20 years, it'll run well