The 2* arena, it needs to stay!
Okay, it's so good! I mean, I haven't used a 2* for over 2 years maybe! So it's great having a use for them!
It needs to stay, it could be a weekly thing, but different rewards, not 10k 5* shards obviously!
It could be 10k 3* shards, 5k 4* shards, 15k PHC shards, 3,600 Tier 2 alpha shards.
It could be anything, 100k gold for the 1mil mark, then 100k BC the week after.
Either way, it needs to be incorporated permanently, if it's weekly it can advertise to all levels of player depending on what you chuck in.
Also it can be an ongoing crystal (collector crystal) which can stay as the game goes on. So that's a win for you!
But it's nice having a use for my 2*s and I don't want it to be another year without using them again!