Mid Lane Options

So right now i'm in a 4 man league, I ended up starting Betsy as my mid laner and he basically let me down wit 15 points. I was wondering if I should stick with him or if I should switch him out. I have Ryu as an alternate, and available mid laners include, Soren, Froggen, Fox, and Power of Evil. Those are the only good ones that i think are available. The other three teams have Bjergsen, Incarnation, Febiven, and Pobelter as an alternate. Also wondering if I should replace turtle with freeze as turtle can be pretty unpredictable and freeze dominated last week. Thank you