It won't be. I've run youth sports league websites on a variety of platforms. The platforms all suck in one way or another (most actually suck in many ways), but that's not the real problem. The real problem is that some portion of the user base/parents are hopelessly incompetent with technology and will consume your time with their problems or questions. Another segment will feign problems to try to get you to do their work for them, and at some point you will do it because it takes less time than spending time on a back-and-forth of questions and getting nowhere.

Just use email and/or text messaging.