Initial impressions: Mutant Void = OP af. Yordles are generically fairly good, too.
Tanky comps tho seem a little underpowered (I literally had a tank comp with bodyguard 6 academy 4 and my tanks just...well, weren't and this was with a three star Leona so like, if a 3* Bodyguard6 Leona isn't actually tanky...tanks are probably weaker than they should be), unless you count bruisers as tanky but bruisers just get HP and the thing making bruisers strong is that their abilities actually give very strong effects (thinking of Cho'gath namely).
Beyond that tho, still figuring things out as I've only played four games.