"It's an alternative to {insert service here}, but if a feature of the platform, an administration, its userbase, etc., are a problem, you can easily find alternatives without abandoning the whole network. Do keep backups of your communities though!"

Also would need to rewrite to not sound as technical, but features-wise, I'd recommend Mbin, Friendica or, once it matures more, PieFed, since all 3 are overarching, being able to access Reddit-like posts, Twitter-like posts, and those compatible with either.