I've been playing Soulstice, past the halfway point. Fun action game with a few weird choices.
Fixed camera gets too close in narrow hallways, which makes it difficult to see every enemy I'm fighting, some enemies are transparent, which makes it difficult to see what they're doing sometimes, and startup animations for non-parryable attacks are a little difficult to spot.
I still have not unlocked all of my skills though, so I'll be reserving judgement until I do that and play through NG+.
GOG is great, but it would be silly to buy fighting games on there, for example, since it doesn't have any infrastructure to support their multiplayer.
Similarly, if trading cards or achievements are detrimental to your enjoyment, stick to Steam.
I stick to Steam for the most part because 95% of my library is not on GOG.