You are completely right. I wasn't expecting the Aiva to be good for CS going in. And, I can't say the Aiva is a great gaming headphones, since the soundstage is pretty narrow. But, it worked out ok for CSGO, being a bit more treble heavy for details, it might actually quite a bit more details that is kinda distracting. Which is a surprising characteristic for planars, since I thought planars are usually darker, coming from Audeze.
Imaging wise, it is great for left/right positioning, decent from the front, but things coming from the back sounded a bit more muddy and unclear, but I think not too much of an issue for competitive play, since most times I am holding 45deg~90deg angles or making aggro pushes, and getting flanked doesnt really happen too often at my level.
However, I am a bit torn since, I was debating about returning the Aiva for the same reason, being tapped after the holidays and its recessed upper mid is kinda annoying for some vocals. But now its performance in CSGO and aesthetics are causing me to reconsider. haha.