@Lovec Krys this is still solvable by building specific wonders for seeds, Elvenar Trade Center and Sunset Tower. I have none of them and still didn't meet with this problem. And if I did, then the solution of event hybrids would be still very easy, since every event offers at least some of them. So I guess such a premium building like Genie doesn't necessary have to produce seeds.
@Marindor one of possible solutions, without including new rewards however, could be (in my case, working for my motivation) removing all current rewards with 25% chance (so overall removing 50%), increasing chance for every other reward twice (to get 100% sum) and reducing expiring time from 100 to 50 days.
If I knew, that everytime I collect I get something valuable, I would rate this building much better, despite the lower amount of possible collections.