First of all, switching styles just because your stats rolled a certain way is entirely impractical. I've never, ever, ever switched fighting styles because of a trans roll. It's too big of an interruption in the flow of combat.
Not really promoting that since I do same style regardless (since magic is stronger). But for someone who has all R1 skills and wants to do that they can if they want max power out of all skills involved. DK is the only trans that gets ALL of the bonuses except def/prot. I think most people endgame end up using magic/melee or magic/alchemy anyways regardless of stat rolls. Also its only an interuption if your pot poisening/speed running. If your just running solo for pleasure switch from one to next isn't a issue.