Not to add to the fire (because i think that the "obscure" spells means house rules etc.) there may be there for bloodlines giving spells that aren't in the sorc/wizard list, like the draconic bloodline giving you spell resistance.
I think it's based on the erroneous belief that being able to choose what spells you cast each round is more powerful than being able to choose what spells you cast each day.
I like the idea of giving Sorcerers their bloodline spells two levels earlier, but I'd say that the bloodline spell should be the only spell they know at that level. Let them cast it twice per day a level early, so that you can keep the rest of the chart unchanged.
The 1 level behind the Wizard progression was made out of balancing reasons.
And it was one of the worst design decisions to take with a Core Class in 3.X. Sure casting spontaneously IS POWERFUL. But this would have been fixed more easily by giving them 1 slot (per day) less than they have currently. Or give them a kind of restriction like the cleric (lawful vs chaotic). Or make them more like bards who need a bonus slot in that level (especially when coupled with the less slots per day) to cast it.
So you would need a bonus slot in the 6th grade to get to cast that spell in lvl 11.
Most people playing Wizards ,note that this especially applies if they have to play him from level 1, will NEVER EVER sacrifice a caster level unless its a special build (eldritch knight). If you min max that may be different, especially with blasters and the crossblooded Sorcerer 1 lvl dip.
So it would look more like this
1st 3
2nd 4
3rd 5 0
4th 5 3
spells per day caps at 5 instead of 6 and you get 0 spells per day at the level the Wizard gets it "naturally".
If you want you can still add some "casting restrictions" like he must decide for lawful/good/evil/chaotic spells... Or whatever
...casting spontaneously from a list of one isn't casting spontaneously.
Sorcerers never cast from a list of one though they always have the option to cast lower level spells with those slots, an option that becomes more powerful if you actually use metamagic.
Metamagic rods are a strike against the sorcerer in that regard, they should be renamed 'cheese sticks', effectively casting spells above your levels with items that are too cheap in comparison, besides bypassing the feat. Both metamagic and the rods could use a significant rewrite.
Arcane Bond is another strike against the sorcerer, once per day they can cast the one spell that makes everything right, if the goal was versatility over power it should probably not include the highest level spells a wizard can cast.
Sorcerers make for very tough undead though that could be considered a strike against the wizard, tohugh really this is mostly for the GM.
Wizards just gets some of his spells for free, most are still going to cost him, human sorcerers are able to get a load of spells at the expense of some hitpoints but at least they won't cost money.
Sorcerers are pretty good at UMD, it can help with some of that lack in versatility, ofcourse that is going to cost money and wizards have better options/more feats to craft them.
* If the sorcerer can cast a single spell per day more of every level or so I do not see a reason to have them stay behind on the spell progression, I also think metamagic is at least as fitting for a sorcerer as a wizard, but they lack they get less bonus feats, I'd rather see the option to take either a bloodline feat or a bonus feat boosting up the progression to the same pace a wizard gets bonus feats.