I agree that the idea of more Costumes is simply a money grab and does not make the game any better. It was a rather good idea for S1 heroes, who got a bit to weak when compared to new ones, but it was all said before. It seems we will not see more hero buffs, just more Costumes, which is a bad idea.
What I would like to point out is how the balance of the game has changed negatively due to new Seasons coming out. F2P and C2P players are having a tough time nowadays. TC20 was simply abandoned with vanilla S1 heroes, which makes it harder for new players to compete without pouring tons of cash into it. Hero Academy takes ages to build and when you make it, you have 7 days for 5% chance for something different than TC20… When I joined the game in 2018 it was quite simple - you had your S1 heroes from TC20, Atlantis S2 heroes with returning HoTM and all the events, it was all quite fair. Now we have 4 seasons and not much has changed, except more heroes you want to have, but will never get without cash. For me to make it balanced again they would need to add Season 2 heroes to TC20 or at least shorten the training in HA to 4 days and make it easier to build it in the first place.