^ You're quite right about Fassbender's accent. The weird thing is that in the movie Hunger, he did a pitch-perfect Belfast accent, which is a lot more different than his own Kerry accent and difficult to perfect than non-Irish readers might imagine. Of course, Brosnan's irish accent frequently came through his 007 performance too and as for Connery... Well, nuff shaid!
I think Hardy has more of the physicality that Bond may require than Fass does. Although they're only about 6 months apart in age, I also think Hardy looks a lot younger than Michael, so by the time Craig leaves, he'd (TH) probably look closer to the right age than MF.
Having said all of that, a Hardy Bond might be more in the vein of Craig, so it's likely that Eon will cast someone different next time out, just like Craig differed from Brosnan, Dalton differed from Moore, Moore differed from Connery etc. (IMHO, Brosnan and Dalton were the most alike back-to-back Bonds)
Like you, I'm quite happy for Craig to remain there for some time yet.