Which on do I need??

[Mikey's250]

Ok I been trying to figure this stuff out so I can get my chip ordered.
So right now all I have done to my truck is AFE intake, 4in turbo back exhaust, boost fooler, and gauges. I have an Edge programmer but Im getting rid of that. My questions are:

If I get the FU package and later I decided to get injectors,bigger turbo etc, will I have to get the FU2 package or can I get the correct tunes on the FU?

What is the best tune for the best fuel mileage?

Im thinking about this setup: 65 mod tow, 80 DD, 100 Perf, 120 race, Lope and smoke show.
Last thing is I pull a 14 ft trailer w/ 2 zero turn mowers most days of summer which is not real heavy(maybe 3000lbs) but I also sometimes have to load up 5+ yds of mulch or sand which is pretty heavy. I dont want to waste a spot on 80 light tow just for my little trailer so is it safe to say I will be fine towing the small trailer with the 80 DD tune or not?