I've been here since Season 3 but realistically, they can not really give us any big goodies like extra money or pops. That puts others in a disadvantage, which also is not fair to those who are grinding too but maybe are just younger and just found this game.
Supporter Features would be something they could easily do for the people that stuck with them for so long. A premium Arena Design as a Gift could be something they could easily do.
There certainly are options without putting others at a disadvantage.