For that specific reason alone, I strongly encourage and definitely hope that in the future other skills will see mastery-style additions to them. Variety and choice is the spice of UO, and what keeps it from being the level grinder that 99% of other MMOGs are today. With that in mind, I have an additional suggestion... one I'm sure I'm not the first to make, and one I'm sure many people would like to see... I would love to see items, particularly clothing items, be convertible -- perhaps requiring a tailor to do the conversions. For instance, half aprons are fine for some people (particularly the old PvP crowd back when they did nothing at all), but let's see the ability to take a Crimson Cincture and make a belt, an obi (I think... the SE belt slot thing anyway)... Let's see robes and dresses become interchangeable (no I'm not going to start wearing dresses, but have to be fair here... heh). So let's continue the trend of "not a cookie-cutter" for characters! Keep up the mastery idea, and expand it into other aspects as well.