Introduce character shards. Add a pool of chars to a ‘supply depot’ called character depot. 100 shards, or less, nets you 1 char, where the one with 100 is ascendable to a 6* char. Each pull, single or big, nets you 1 character shard or maybe 2 and give 1 from elite tokens pull, and maybe some from a prestige/ 5* token pull.
It gives people the feeling that the premier pulls are actually less of a RNG thing. The less lucky ones among us, can at least get an ascendable 5* from the depot. I have seen these kind of things work super well in other games and it really encourages people to spend money and it feels more fair as we do.
Ofcourse the char shards could also be earned through events, for example wars. Give them out to the servers who score best in cross region wars. It will make sure that the factions on servers work together well.