LL Increasing the MPR from 2 innings and an AB. Kids will quit because they're bored sitting on the bench and not being part of the team. Too many daddyballers in it just to make sure their kid plays up the middle and sticking the spazzes (for lack of a better word) in RF. That may be the biggest turnoff and where you lose potential ballplayers just starting out in LL. Having good people run the local leagues and coaches who teach the game and keep players interested is the key. It's not gonna work for every kid but it will for those kids who love the game that just need a fair shake to find out if baseball is for them..
Also, LL has too many regulations and restrictions regarding all-stars and most of the better players are looking for more baseball to play. Travel fills the void.
What league ball has in it's favor is it's still the cheapest way to play organized baseball where some travel leagues cost a lot of loot.
As for high school, Travel hasn't taken over the high school season in our area but it has changed the landscape of summer baseball. Top HS players are moving away from American Legion to the various travel teams around the state. There's also a newly formed summer high school coaches league which is only for players entering grades 9-12. They play in a summer league for their high school coaches and the top players from the coaches league play in U-17/18 showcases. Graduating seniors and college freshman play U-19 Legion and younger players from high schools who's schools don't participate in the HS coaches league. This coaches league I see as a good thing because it keeps more high school players playing summer ball and they don't get squeezed off Legion rosters by the return of college freshman. I would imagine this has some negative affect on Babe Ruth baseball because of the available summer leagues now open to high school players. I'm guessing, but this also probably leaves more spots open for local rec league players who don't make the summer Babe Ruth team in favor of the underclassmen high school players who now have a new league to play in.