I must admit that I am not currently using these rules in my campaign. I believe that Vrylakos is, however, and he posted a character sheet for one of his characters using this class on his webpage. IIRC, Lela is using it as well.
As to the two additional sorceror spells: when I wrote the class spell progression, I assumed that the sorceror would choose two spells of the highest level available to them. Assuming that, the sorceror ends up with 5 first level sorceror spells known and 4 spells known of every other level. Sorcerors come out slightly ahead of the PHB sorceror in the deal but since the domains are themed, there is some duplication in them (thus reducing the overall effective number of powers available to the sorceror) and a number of suboptimal choices for the spell level (again, reducing the relative power of the sorceror who tends to do best by cherrypicking the most powerful and effective spells of each level).
On the whole, I suspect that the domain sorceror compares more favorably to the wizard than the PHB sorceror, but I've always been of the opinion that PHB sorcerors got the short end of that stick.