I'm wondering if they're going to simplify the PvE endgame. People bitch about ToA, but SI endgame PvE items are also pretty gamebreaking, especially if you use them in ways they're not intended. The Albion cleric chestpiece has a ~1200 HP HoT heal reactive proc, which is more than half your HP total. It's not so bad if you equip it on a cleric, but put it on a melee class and it's a problem. Without buff bots it's almost impossible to actually kill someone wearing one of these 1v1 as a melee class.
It's hard to say what class to pick without knowing exactly what version they're using. But if they're using Old Frontiers RAs and the state of the game just before ToA release, play a Paladin. Get ACTool to twist your chants perfectly, you have super-easy leveling and you'll be bonkers overpowered in PvP. If nobody has buff bots and you can get a Sidi chest you can pretty easily 1v4 groups of stealthers.
Also, if you're going to play any kind of caster: Pick the race with the highest starting Dexterity and put ALL your additional creation points into Dexterity. Cast time in DAoC is based on Dexterity and spells in DAoC have breakpoints where being above X amount of Dexterity makes them cast like 25% faster, doing this is the difference between 1.5 and 2 second cast time spells when fully buffed.