It just allows guys who are running their old NBL despite being in the ML to continue to run them. Keeps activity up in the NBL. Its up to you though ultimately.
I have no preference, in fact I keep having to reference back a page just to say which team I want in this post because I can't even spell the cities. I'll take the pork brawlers because they sound delicious.
Not yet. There will be some other NBL openings when we transition to OOTP 15 (virtually the whole NBL league).