I hate pets and my magsorc has a pretty good setup that actually beats what I get with pets.
Oakensorc HA build made for solo PvE work. Gear is Sergeant's Mailx5, Mother's Sorrowx5, Oakensoul and Slimecrawx1.
Companion: Bastion as a tank. I want a tank so my sorc doesn't have her HA's interrupted. Bastion has the Searing Weapons skill which boosts my HA damage by 15%; focusing on quickened/augmented traits gets the uptime on that up to about 60%. Having a tank companion means you want to have a 'heal others' skill like matriarch or vigor.
Skills: Vigor, Bound Aegis (passive minor resolve which Oak does not provide, and passive magicka), Caltrops (breach), Wall of Elements, Lightning Flood. Ult is Dawnbreaker for the passive damage; I never cast it so I can rely on nearly 3k passive healing from the Strategic Reserve red CP. I've tried numerous no pet skill line ups and this one works out the strongest for me.
When I ran pets, it was the same gear but slotting: Twilight Matriarch (need heals for tank companion), Volatile Familiar, Daedric Prey, Bound Aegis, Caltrops (breach), Dawnbreaker.
My no pet setup slightly beats my pet setup but I confess that opting for Matriarch heals over Tormentor damage likely reduces dps in order to have the stability of a healthy tank. I suppose I could dump the tank companion but then I fear I'd have to interrupt my HAs much more frequently. Also, as I said above, I hate pets. Flappy is huge, in the way and when I send my tank to engage, Flappy pulls aggro before the tank can get to the target. And the purple monkey is so ugly it makes my eyes hurt.