ANALYSIS
So just to make sure I wasn't imagining things, I made an Excel spreadsheet comparing the Sorcerer and Wizard from levels 1 to 20. They're close enough in build you can do a simple arithmetic comparison.
Here's how it plays out-
The have the same number of Saving Throw proficiencies. (duh)
They have the same base number of spell slots.
Wizard has Base AC 10, Sorcerers AC 13. But with Mage Armor, meh.
What do Sorcerers get that's "more"?
1. +1 HP/level
2. 1 extra Cantrip (until 17th level, when Spell Mastery puts the Wizard ahead of you here too)
What do Wizards get that's "more"?
1. Wizards have way more spells known just using the base rate of 4 + 2/level. And that's the minimum, given that you can capture enemy spellbooks and such. It starts out with a 4 spells known advantage at 1st level and goes up to 29 extra spells at 20th level.
2. Wizards have more spells prepared at all times. So they can recreate any given Sorcerers' spell list and then have even more spells in addition to that. The advantage is 2 spells prepared at 1st level and goes up to an additional 12 spells prepared at 20th level.
3. The Wizard sub-class abilities are very similar to Metamagic and come in at the same rate and Level. But the sub-class abilities are free to use, and Metamagic uses SP which reduces spells/day.
4. Wizards get more Spell Slots/day under almost all circumstances.
If you convert all Sorcerery Points into Spell Slots, this works out to equal Arcane Recovery from levels 1 to 5 and then is better than Arcane Recovery from 6th on up. But only a little. You effectively get only 1 extra spell over what a Wizard gets per day, but it's not your highest level (i.e., at 17th level you get one extra 4th level spell over a Wizard) and it's at the cost of all of your Metamagic.
If you use your SP for Metamagic, the Wizard's Arcane Recovery means that he always has more spell slots per day. The Wizard basically end up with 1 additional spell of their second-highest level per day relative to the Sorcerer, at every level.
And that doesn't even account for Ritual Casting, which adds even more Spell Slots/day to the Wizard by letting him cast utility spells "for free" in many situations.
SUMMARY
So wizards get more Spells Known, more Spells Prepared, more Spell Slots/Day, free Metamagic, and Ritual Casting, which Sorcerers get +1 HP/level and 1 Cantrip (until 17th level).
This doesn't seem very balanced between the two classes.
SUGGESTIONS
There's two ways you can go here:
1. Modify for parity
2. Emphasize the differences
If you want to Modify for Parity, wizards only have more spell slots/day when Sorcerers spend their SP on Metamagic. If you make some of the (less powerful) Metamagic free to use, then spell slots/day should balance out just fine.
The main disadvantages are Spells Known/Prepared and Ritual Casting.
1. Let all Sorcerers have a Book of Shadows just like a Tome Pact Warlock.
2. Create Origin Spells for each Sorcerous Origin which are free to know. You would need at least 2 spells per spell level to maintain parity with the Wizard.
However if you want to Emphasize the Differences, I think you need a lot more spells per day to make up for the lack of spells known/prepared. The easiest way to do that would be to tinker with Sorcerery Points available and also Sorcerery Point costs.
1. Give them some Metamagic for free, and "all the Metamagic" at SP cost.
2. Buy spell slots at cost of 1 SP/Spell Level.
3. Add Charisma Bonus to your pool of Sorcerery points.
If you do all three of those you end up with 2 more spells/day of your highest level, or an equivalent number of lower level spells.