Personally, I think the wide selection of items did the trick for me. Single-player native is not bad, but multiplayer native has sooo much less equipment. Also, from time to time, it forces me to play roles I don't like: vaegirs, khergits, things like that. Here, I have my custom equipment, things that I like: big shield, nord looks, throwing axes - in native, I can't always use these.
Also, being in 80-120 battles is sweet.