Hey Carl, first of all, awesome server. I've been playing on it for a few days, and I have to say that it was a very awesome experience.
One slight thing I noticed however is that the mini-map icons and name tags made things a little cheaty in regards to spotting players.
For example, the other day, my temporary base was "raided" by RedHerring, but was able to spot him hundreds of blocks before he actually came, thus allowing me to secure all of my stuff beforehand, despite him being invisible. I spoke with a few other players and they agreed with me, so we were wondering if it was possible to make the name tags and player icons disappear for everyone, at the very least while a player is invisible. Perhaps reduce the range of it?
If so, could you put it up for a vote? I think it would really make the experience a lot more intense and interesting when you can't see enemies coming from miles away. Perhaps it would even encourage people not to move 100000 blocks away from spawn.
I know it is a bit ironic to be defending the person who raided me, but I do believe in all fairness that he should have caught me more off guard.
Anyways, if it isn't possible, it isn't really a big deal, just a little suggestion to improve the game play.
Also, regarding the factions, I'd lean towards removing it. Warded blocks and force fields should be sufficient land claims.