Everybody online said the non-plus-ultra was the iPad Pro, even compared to other name-brand devices from Samsung/Microsoft.
So I tried them both, and wow. 120fps and a screen optimized for low delay really makes an enormous difference.
With all other tablets, it was more a question of "well how more or less awkward does this feel to use", where that question didn't even come up with the iPad.
I know this sounds like shilling, but I recommend just trying it out on a real device sometime, even or especially if you have no intent of buying one.