I think that's a personal decision and nobody can influence it. You know whether you want to stay or not. If you stay, you will have to adapt to the new rules. Because you have to accept it, the past does not return.
Not really if there are many cheats in game. What I do see is that there are people that since I know him never put a single $ in the game and now appeared with all mythical, until the modules. Let's face it, you don´t get that with coins, even if you have billions. You get that by buying hundreds of premium boxes. So I have that doubt.
With regard to "donors", they are players who have bought a lot. As such, they have built very good mechs and that allows them to keep them on top. They are exposed as anyone to lose or win. They win a lot because they bought and have good mechs. Fine.
Then ... as we have said here many times, this is no longer a game of intelligence and strategies, but of force. Any monkey with guns can win if they give him the best items. Much they that in the previous version of game lost a lot, now you see them in top, only because they bought a lot and have the best in their mechs.
If you stay, those are the rules. "That's all folks"