Me and my friend were on New Vegas and were thinking of armor customs. as add-on to a DLC you could have armor customs from the armor already on the game wether its an extensive custom or just a change in color it would still be a great add-on like having diffrent topics to choose from like mods for your armor. With this being able to change who you work for like making your custom with NCR stencled you get attack but due to custom it dosn't affect your trooper buddies in the NCR or your Rep with them.
the armor offered by the van graffs guard has been a favorite of many because its diffrent. the legion vexillarius armor would look good as NCR and maby some legion loving people could make NCR ranger gear into there one of there own.
the way of attaining the armor would be to go to a certian person in the DLC and you would need the mod you want or the pieces you want to interchange and pay him 500 caps to paint or customize the armor would of couse need to be at full repair to get a customization