I would like to add some comments that might help you with your build: Hoard Gullet seems somewhat... less than useful when you can just buy magical storage containers, Enlarge Person is obsolete when you start polymorphing, and learning AMF without a means to shape is a waste of time.
Recommendations: Ditch Hoard Gullet and Enlarge Person. Ditch Weapon Focus and take Extraordinary Spell Aim so you can cast AMF (Incidentally, you have this as a 7th level spell. It is not. Move it down to 6th and replace it with Limited Wish because Limited Wish can be used to emulate Psychic Reformation and allow you to rechoose your spells known in one standard action. Get rid of Disintegrate in order to make room. Or ditch AMF.) and exclude yourself from its effects. Use Shapechange in place of Disjunction.
And for Pelor's sake, grab some teleportation. It gets you out of Forcecage just as well as Disintegrate, but will cost a lower level spell slot and can increase your mobility options significantly. Dimension Step, Dimension Door, and Teleport are good choices.
If you want to counterspell, it is easier to take the Improved Counterspell feat and Heighten Spell rather than simply picking up specific spells to counterspell as there will be so many Spells that Do Bad Things out there. Applying metamagic to a feat is a full round action; you can get around this by using the Metamagic Specialist sorcerer variant from the PHB 2 or the Rapid Metamagic feat. You don't have many spare feats, so let's ditch Divine Companion for Metamagic Specialist.
Honestly, though, I suspect it's a bad idea for a gish to be counterspelling at all...
Take the Heroics spell which grants a fighter bonus feat for 10 min/level.
New feat lineup for Counterpelling + Metamagic Specialist sorcerer:
Otherworldly
Combat Casting
Power Attack
Heighten Spell
Improved Counterspell
Extend Spell
Persist Spell
New feat lineup for Divine Companion + AMF sorcerer:
Otherworldly
Combat Casting
Power Attack
Extraordinary Spell Aim
Extend Spell
Persist Spell
Reserves of Strength
Just to be clear, is Otherwordly there just so you can engage in Alter Self shenanigans at low levels and Polymorph shenanigans at higher ones?