I just don't rate Bastareaud. Sure he's powerful, but he has nothing else to his game. At least Tuilagi and Kuridrani have other facets to their games besides being powerful.
Henshaw is the current 12 for Ireland, although you could argue he's more of a 13. I probably wouldn't have any England 12s on my list, they're all pretty average. In Barritt's case, I think much like Bastareaud he is a 'one trick pony', i.e. his defence is good but few other areas of his game are international standard, and that holds him back from being considered a top 10 inside centre for me.
I'd probably say something like this:
1) Nonu
2) SBW
3) De Allende
4) Giteau
5) Fofana
6) JDV
7) Toomua
8) Roberts
9) Henshaw
10) Leali'ifano
2 to 4 are very close and are interchangeable in my mind. I felt unsure on where to rate JDV, as I don't know whether he will be the same player after such a horrible injury.