More Rats, Less Yordles

Unlikely to happen. Yordles are a species by its own (or a class of spirits if the rumors about the lore update are true). Twitch on the other hand is a mutated rat from Zhaun, the place where chemicals are filling the air. Twitch doesn't represent any given race in runeterra, he is an accident, a mutation that happened by coincidence. It would be strange if more of his kind would appear.

I think it is better to keep twitch unique.