Arcane brilliance: Same as arcane intilect except lasts 1hr compared to the 30 min and is a party buff. Does use arcane powder but that stuff only costs around 9s each. This is used for party quests and instnaces mainly...i guess it could be used for soloing but uses up the reagants...
Highest lvl of water: does 4200 mana in somewhere around 30-sum seconds....much better then the lvl before. Get this as soon as you can. To get it you must go to the elf library in DM........i got to it alone when i turned in the quest so its possible. Once u get in go straight and the elf is on the left. All the quest is to kill the Hydrospawn....pretty easy.
This is jsut an opinion since im not a pvp expert....get armor with as much stamina as u can...
The Crystal Water quest is difficult, but it may be possible solo. You will need the Cresent Key from the damn imp (Warpwood Quarter, east). If I'm on you can ask me for directions (and if I'm 60 at that point, I'll help).
When choosing PvP gear, two stats are most important: +dmg & Stamina. You need to survive Rogue's Stun Locks, Warrior's Charge & MS, as well as Hunter's Aimed Shot. They hurt, belive me. The +dmg will be very usefull in taking down the other guy, as it really ups the crit damage too. For heavy fire spec, you may want to focus more on +crit though, due to Ignite.
Intellect doesn't help you much in PvP, as you will rarely use your entire mana pool. Either you'll get smoked right away, or you'll killl them quickly enough that you won't use too much mana. There's always your mana ruby too. Just completely ignore spirit for PvP, out-of-combat drinking makes up for it, or you can just die in the BG's or Group PvP to get your mana back.
60 Warrior (H), 70 Shaman (H), 70 Mage (A), 70 Rogue (A), 7 Priest (A). I play every class. I *had* too much time on my hands... Feel free to ask for advice. If needed, I am willing to use my Alliance characters to help with non-instance quests. Just let me know.