starting a new campaign?

[leonpoi]

I would personally do the v1 timeline, or that kind of era anyway. However, since you're using the t2013 rules there will be a lot of equipment (sights etc) that may not be appropriate.

For me, personally, I like the 90s timeline because there still are a basket case of weapons and equipment and armed forces are in transition. If you set it in the 21st century, well equipment can be more advanced, but I think less varied (at least for regulars).

Otherwise I'd do some modern small-scale thing militia vs occupying force in a post apoc takeover of a small town.