Bone Stock 2007 Ram 2500 5.9 Hemi Mods needed

Hello everyone;

I have a bone stock 2007 Ram 2500 5.9 and I'm looking to pep it up for towning and a couple miles per gallon better.
1st... I have just a Superchips tuner.
2nd....What is the best/good bolt on cat back Exhaust
3rd....Do I go with a drop in filter or a cold air package
Any and All help would be used.

Thanks Clifford