The quanta cap is kind of a mixed good/bad for me. yes it minimizes insta kill situations kind of. if Someone has 75

they play a couple of lances it's still game over.
75: fire + 4 lances = 96 damage..+ Fahrenheit + 20 more damage. Stone skin was changed to X with no limit due to 75 being its limit already. It prevents people from playing fractal + lots of high cost dragons to some extent.. you can only play so many now instead of saving up well beyond 75 to play a field full in one turn.
It limits the creativity that could be used with having 75+ of a quanta type which isnt all that horrible, but makes cards like soul catcher, solar shield, rustler etc that produce extra quanta for you less likely to be used i think due to pillars can give you enough to 75 without the extra help. my rainbow deck gets 75 of all 12 elements in any middle range length of a game no problem. This new shard coming out though im not so sure its a good idea.

shard + blackhole or pestal decks = new quanta ever... plus if you do manage to get some quanta say via supernova.. if pests done eat it all your limited to how much you can try to save up.