It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

I've seen a lot of MP Mods but are there any single player expansions/alterations? Recommendations? Personally I was hoping for enhanced combat/force powers.
Bit late with responding but have you checked the JKhub?
There are a couple of smaller SP maps/campaigns that I know of and there is a total conversion called the Dark Pastime in production but that seems to be the extend of it.

Sadly the series never attracted a lot of modders to do big expansions, probably because of the effort it takes.