Personally I think the idea of more gear is a good one. You just make LS/DS have gear that is comparable to each other and it has a very specific look that would denote LS/DS. Also, you could give a bonus of some kind, but again, there would be something comparable on the opposite side. Maybe seed the gear with +Def for light, and something else of DS.
And make them modifiable!
Lvls 1-3 relics only
Lvl 4 relics and armor
lvl 5 relics, armor, and weapons