Welcome to the game.
Since you're probably still in the middle of leveling your basic knights, you're probably running low level maps (like 2-1) and farming manyus on secret gardens - therefore you don't need any powerful units right now.
I'd advise you to wait for a ticket gatcha. That's a special one that gives you a 4* guaranteed ticket for every single pull and a 5* guaranteed ticket for every 10+1 pull. In the end these are the only gatcha to go for if you're not planning to spend any real cash on the game.
It is true that you could get something good with a pull right now, but nothing is guaranteed - worst case scenario you'd get 11 3* girls. You can get a few 4*, but having a 5* in that draw is already considered lucky. With the ticket gatcha, you have a 5* guaranteed on a 10+1 pull (since you get a ticket to use, that would actually be a 10+1+1 pull).