Your mileage may vary depending on your group setup. I usually get something like Brig, Assassin, Dirge, Illy, (Troub/Ranger/Bruiser), and can usually get away with going to town with the Dogwood Staff on trash with my only heal being a macro that says "/gsay Proc Lifespike more, bitches!"
A mage group full of chokers is bound to be more of a challenge, and the Star of Malice is very highly recommended. Inquisition helps too if the mages aren't pansy cowards standing at max range, and are in meleeing like they should be (encounter dependent, of course.) Aside from that, casting your group heal every now and then should suffice.
As far as debuffs go, for trash mobs and easy named I'll cast Condemned on pull and leave it at that.
There's 3 ways I see to alter the balance between DPS and heals - Weapon/Secondary, Armor/Jewelry, and Stance. All 3 should vary depending on the difficulty and requirements of an encounter.
There's 3 obvious setups weapon-wise. 2H for max DPS (Bonecrusher, Dogwood Staff, Thex Mallet, etc.), Mythical + Star of Malice for fights that need more healing where you can melee, and Mythical + Shield for max healing at range.
I have 3 different gear macros - Max Heal, Max DPS, and a combo of the two. With all of the crit, DA, DPS, and Haste bonuses we get, I focus on getting STR, procs, Base damage, and a modest amount of +CA damage on my DPS gear. As you're using the INT line, instead of AGI, you probably have room to get a little more DA. Some recommended items include Circle of Necrosis, Signet of Betrayal, Melodic Stone, Dreamer's Scale, Soulshattering Band, Soul Lancer T2 Shard Armor (Shoulders + 3 set bonus), Void Soaked Peacock Feathers, Dangling Skull Bone Chip.
Switching stances from offensive to healing is the last thing I do to increase my healing power, because it just kills your damage output. Not only do you lose the bonuses from the offensive stance, you also lose the bonuses from Litany of Combat when in healing stance.
On joust fights, if you know the encounter well and can get away with jousting without it being detrimental to your group, then by all means joust away. Of course, if you're in heal stance, using the Mythical, and are healing a high DPS output group, the death of one of your groupmates will likely cost the raid more DPS than jousting in gains you, so proceed with caution.
So to summarize, O stance, more STR, gear macros, 2H if you can, SoM in offhand otherwise.
I'm sure others can give better advice, as I've only been raiding on
my Inquisitor for less than 3 months (though I can tell you how to play a Conjuror like a pro!)