Just my opinion but...
Getting XP on death is an excellent idea. I imagine it can be pretty frustrating if the same person keeps whipping your tail time and time again, only to get stronger while you stay the same. It seems like it would be hard to keep newbs without some incentive to keep trying. Maybe something like 25% of the XP your opponent gets, but none of the GP.
Spawns are also a good idea. I had thought of this a while ago but said nothing of it. If you are alone on the server, you need something to keep you occupied till someone else comes, not to mention the opportunity to grab a little XP or GP. Like Wandera said, the more people on at any given time, the more likely it is that new people will come and oldbies will want to log on for a few good fights. Maybe some "sentries" in each elemental fortress would be good too. Not too many, to cut down on lag, but maybe just a couple of them to give you something to do if there are fewer than a certain number of people online. They could spawn on player entry so you don't have 8 (or whatever) of them at a time. You should get double XP for ones of opposing alignment, especially since you have to deal with all the damage just from being there in the first place.
And about killing yourself for XP on spawn points and such, it could be scripted to check to see if the last attacker was a PC. If so, XP. If not, nothing. It could check to see if it was a spawn, too.