Can’t go wrong with that one.
I assume side cards is like a side-deck to use between matches in which case I dunno how that would go exactly, it could definitely be useful to tech in certain cards once you know what your opponent is playing and they could do the same.
The only problem is unlike tournaments (correct me if I’m wrong though), you know what archetype your opponent is playing once you have already gone against them once in the best 2 out of 3 round one.
Would also be too slow for anybody to want to do compared to regular ladder.
Don’t worry though, @ThanatosNoa, will be announcing new game modes soon, multiple , so keep hope.