Your link is dead, so I can't comment on the XT hub since I've seen them listed with three different model numbers (M756, M765, and M775). Although all three are a upgrade over the M475 though only the M756 is six bolt. The Blunt is a nice rim, reasonably light and wide at the same time. I have no experience with converting them to tubeless but I've read they work fine.
Well those are M629 hubs which are basically SLX level hubs. The freehub body is 32 POE which is nice (your M475 hubs are 16 POE) and they are plenty strong. The centerlock rotors will work fine with your existing brakes too.
I have xt hub with blunt rims, love the rims but like i have found with every shimano rear hub i have owned more time maintaining them than riding them. I have them as singlespeed so i give them a hammering. Just replaced the hub with a king ss. The xt is well, just a hub.