Movement trays were never used for the SBG. They were part of the separate War of the Ring game that was intended to use the same figures in a larger mass battle game.
How many models/points is your "standard" game.
I don't know that there is a really universal "standard" game size. It does seem like 500-1000 points is a pretty common size.
Is anything changed rules wise in this new release?
This new release is just a compilation of figure stats and scenarios for the second and third Hobbit movie. We are still using the same Hobbit hardcover rulebook that was published when the first Hobbit movie came out. That one was not terribly different than the preceding Lord of the Rings hardcover rulebook. It introduced some additional weapons special rules, tweaked the monster rules, and a few other minor changes.
I remember elves in combat were broken(as the game had a lot of problems) cause if they rolled a 6, you couldn't beat them. Is it just being released again and everything is the same old same old
I'm not sure about elves in the War of the Ring rules (never played it but I did hear it had some problems) but elves are certainly not broken in the SBG. They have good fight stats and some of them have good armor stats, but they are balanced by being expensive. Certainly one on one against a goblin they will win almost every time, but they should not be fighting one goblin at a time if the goblin player is any good.