Coming from Victorian London, Thomas will be very vanilla at first.
However, with the right persusaion, he'll be willing to do most of the things on the yes list-- they're more eventualities than something he'll do with you the first go in bed.
A power bottom-- it's more the mental than the physical, really, and even that is more about power play than anything. He's not going to swoon, but he isn't going to be so upset about some (consenting) rough treatment.