The problem with Jael is that she requires so much support to be viable. You pretty much have to play a Canaanite defense with her, or a large Red offense with TaS/Battle Cry/CoA/etc., or both.
Ish, on the other hand, can win games almost by himself. He works well in an all-Red deck, or in Sam or Purple variants where the Red is splashed. FS on him is so good.