Really good. The teams origin was pretty standard but I'm really liking the teams interactions with one another. Jeff Lemires writes everyone they way they should be no one sounds like there out of place winch is great. He also doing longer style arcs with each arc being 7 issues or so , so everyone gets some good screen time.
temporarily and permanently? I think it would be cool if Flash and Orion(separately) join them for an arc. And I'd like John Stewart to join the team since they seem to tackle cosmic threats and Stewart is a GL.
I would like to see Guy Gardner as a Red join the team. He and Supergirls interactions where great during the Red Daughter of Krypton arc.
And going by Futures End I think a few of the Legion of Super Heroes members will be sticking around but I like the team as is. 7 Core members with other people helping out as needed.