You should really work towards evolving some girls. They get a small boost (or loss depending but very minor) for getting evolved but the big thing is you can get them to lvl 20-30 really cheap/fast and that's a huge stat boost.

You can use the lvl 20 Manyus all the way to 50 and should be fine on money. I'm at 820k coins and mainly did 2-1.

With the 3* i wouldn't bother going higher then 30 since you should have enough 5/4*s to work towards evolving. You should be getting another 5* on Thur/fri from event to.