This is exactly why im tempted! All i see today is archers and the odd mages. I normaly play a mage but its impossible to play on my current connection. So that leaves:
Tamer (hate when other use it, so im not that tempted)
Dexer
Archer (probably wont happen either, just hate it)
I love dexxer PvP. I have my PvP mages, and to be honest I much prefer the dexxers. Firstly, the skill required to play mages is highly overrated, IMO. But most importantly, mages have to run from dexxers and take advantage of connection issues to win (the famous "circle run" where you can't actually see where they are and have to guess, as a dexxer). I have played mages in every other game in my life going back to AD&D when I was 10 (I'm now 39), but I have always hated playing UO mages because I hate running from people and I hate taking advantage of a non-game issue. Just MO, not trying to start a big argument here.
In regards to playing a dexxer, I have to say your connection issue is going to be a problem. To play a dexxer you simply MUST have as good a connection as anyone else. If you have a bad connection, you can't close the distance, which is obviously necessary for dexxers. You might have to go with archer if your connect isn't good enough. If someone is running away, pursue and you will always eventually catch them. If they don't have to stop to cast something, they'll still eventually run into some bramble or something that slows them down for a split-second, and that's really all you need.
In regards to your template, I think no Resist is going to really hurt you, especially once people figure out you don't have it. In a random dust-up it might take a while but in this game you run into the same peeps more than once, and they tend to remember who has Resist and who doesn't. Not only will you get mana vamped, but even with a box you can be para-ganked by only 2 people. You will have huge problems with necros, like 30 point Pain Spikes, 20 second Blood Oaths, and other nasty stuff. I haven't a clue about Mystics (coming back to the game after 2 years away) but I'm sure they have a way to attack non-Resist players. I strongly recommend you find room for Resist, probably by dropping Chiv (though 55 Chiv can be good, and 75 Chiv also to add Divine Fury) and dropping Tactics to 100 (or 90), Anatomy to 80 (or even 61, who cares if you can rez but you need to cure poison), and maybe Healing to 90. You be the judge but those numbers are workable and will free up skill points for Resist.
You might also consider Ninjitsu, if you solo PvP. Otherwise you will be Dismount-ganked all the time. It's also very nice to be able to DP from a distance with shuriken/darts. But this might be a luxury and isn't really necessary if you PvP in groups or with partners.
One thing to consider is that dexxers DO have a ranged attack in GE pots (or Melisande's Fermented Wine, if you can find them, which are about 50% more powerful than GEs). Set a macro that fires one off and can hit peeps on the run (or if they get stuck). I've probably finished 50% of my dexxer battles with a GE in the back as they're running for their lives. If you have an ecru ring on, all the better, but it's not a requirement.
Another thing to consider with dexxers is that their weapons are very fast compared to archers, so you can be creative with your armor. You don't need 180 stam to get max swing speed like archers do, so you can put stuff like HPR or Reflect Physical on your armor instead. I'm putting together an HPR/RP suit for my guy, and can't wait to try it out on all these archers with their Quivers of Infinity (100% physical damage conversion).
If you have Bushido, you can ride a Lesser Hiryu. I recommend this, and have it guard you so it attacks anyone who Dismounts you. Dismount is useless in 1v1 so anytime you're Dismounted you can expect a gank to follow. The Hiryu helps and buys you some time. Train it up so that it's most effective.
I have also found it useful to add "attack last" to some commonly used macros (like Lightning Strike or Curse Weapon), so you don't auto-attack whoever attacks you and spread your damage around. You wanna focus on one guy until he's dead, dead, DEAD. If he runs, all the better, he's leaving his support group behind.
I should also add that, while I personally find Disarm cheap and refuse to use it, it's quite useful against other dexxers, if you're so inclined.
Weapons-wise, carry a bunch for the specials in case you find yourself in a 1v1 against another good PvPer. You need to have the ability to get creative. However, 90% of the time you want to go in and kill as fast as possible. That means 3 consecutive AI's delivered over the course of 2.5 seconds (hit - 1.25 sec - hit - 1.25 sec - dead). Make sure you have the mana for this. I personally like the leafblade as my main weapon, because I solo gankers and Feint goes a long way towards keeping me alive. You also need a way to stop their healing, so make sure that if you don't have Ninjitsu like me to have the other special be poison/bleed/mortal. Kryss can be very good, as can Hammer Pick. Cleavers are nice but make sure you have an AI weapon to switch to after 2 hits with cleaver. I don't like switching so much but others are cool with it. Remember you can only do 2 actions per second so switching can slow you down (my biggest problem is trying to do too much too quickly).
If I think of anything else, I'll chime in, but I think I've covered the basics.