10Us and 12Us can be good for a pitcher to dominate, but one thing I've found in my TB travels is that everybody hits in 14s. Be cautious in what you ask for, could be a start to an END, if you know what I mean.
I've seen a number of "Golden Childs" at a young age that have turned out to be sub-par softball players later in their teenage years. Wind up in D-II or D-III or maybe if lucky a Low-Level D-I.
As you will see, there are many varying opinions on this forum. The best thing to do is look at the tryout schedules and plan on attending those of teams that interest you. You need to be the advocate for you daughter and do what is in her best interest. If she's looking to be a pitcher on the higher level teams, find out how many pitchers they plan on carrying. If she's happy to continue to develop her skills and play other positions, there are teams out there that can meet those goals as well. Truly the best advice is to watch potential coaches / organizations at tournaments and determine how your daughter will interact with them. Make a list of what "you" are looking for your daughter: in a team / coach / organization. Remember not every coach or team is right for everyone, but you will have to do your homework. Good luck to you and your daughter. There is a team out there for her.