Forget the whole "which sport is better than which" shit, stray from opinions of others.
You say you've been playing baseball for a long time. Despite the pain (which could be remedied, look into it), and the losses, it's still a sport that you've enjoyed much of your life. It may not be as fun due to the aformentioned shit and just getting burned out. However, years down the road, you'll be wishing to play it again. It's engraved in ya. You rarely see somebody simply drop a life long passion and without any remorse. You could try playing through high school and perhaps college. If you stop, that's pretty much it, and that'll be that, but I bet there will be some regret later on, and/or a desire to play again. Lax on the other hand would be new to you and the consequences of leaving that sport would be nothing like that if you stop playing baseball; there simply isn't that long connection. As some of said, you might not even get the chance to play much at all.
I'd say stick with it. Get your arm seriously checked out, strenthen up, and go for it. It is one of those sports that's hard to play when you're older and past school, compared to something like tennis, heading to the mountain, etc, especially if you're pretty decent and competitive.
Sorry that wasn't very eloquent, been a looooooong day.