Outside of getting in your zone and casting rythm, as well as managing your power, the group setup is HUGE.
Practice practice practice (EH trash is great practice fodder) your dps in whatever group you get placed in, then push to get put in caster group with troubador and wizard. If you can get consistant you should be able to top the parse now and then or if good, top the parse alot.
A good or great illusionist in this type of group pushes ALL the dps to higher lvls. So many people out there have this misconception that we are buff bots. SO WRONG! Sure, there is only a tiny fraction of GOOD illusionists out there, but when you get good, there is no other class like it!
If you want to come close to maximizing raid dps and have a sick illusionist group, get with the raid leader and convince him to give this a shot. Illusionist, Wizard, Troubador, Healer (Templar or Fury is great, but any healer would work), Summoner (w/ casting pet) or any other caster, and good target for haste/IA (I like Swashy). This group setup allows for you to buff wizard with TC and a melee with IA/Haste. This also allows you to drop group int/wis buff, synergism yourself, and cast your pet (I drop pet for certain named fights). If you want to rationalize being able to cast pet instead of 3 synergisms you better get with the troub and the wizard and make sure they cast Precision of the Maestro and Frigid Gift as much as possible.
If you are really good, you will find yourself winning some zonewides and pushing the raid force to parses they might not see otherwise. I know I for one keep the assassins, ranger, wizards, and others on their toes.
We may not be a spike damage class, but if you keep at it, hone your skills, and are consistent you will see some pretty high numbers. Numerous times tonight in EH I parsed over 3k, best being 3400+ (1:16 fight).
I can't wait to get more proc gear! Note: Finger Bone Manacles suck balls. It may be contrary to the procs>crits>boe, but i'm probably going to replace them with the bracelet from Wuoshi's heart if I don't get Nizara Sash or Matron Bracelet 1st. One more piece to go to complete fabled set. I will most likely use the full set, even if I was able to get sage gloves and breath helm (I have enough mana options that i'm not concerned about mana proc gear).
Good luck Illusionists, don't to many of you get uber or we will get nerfed!
-Gerrod