Re: Not played in a long time.
Welcome back.
1 - tweaks and fixes for the most part. The online league has reached new heights with a top team of people behind the scenes and very much worth a look.
2 - I would play combined, better horse development in my view due to the 2yo time on the flat, horses arrive at 1yo and end of the day it gives you both, you can still specialise for NH.
3 - ask as you go, and lots of good stuff on the forums.
Josh