You can get the same parts more then once per transfomation

[laserpointer616]

it's a little annoying. also how do I move to a new character if I want to try a new one without nuking my save

[ArcDragon]

You can get the same parts more then once per transfomation

Not sure I understand. You should only be getting one part change per transformation, but it's possible to have multiples of the same type of part. For example, horses have two pairs of legs, spiders have four, etc.

how do I move to a new character if I want to try a new one without nuking my save

"Save and exit to menu" on the left-menu will return you to the character roster. From there, pick another character slot. Note that slots 2 and 3 need to be unlocked. Talk to Rina at the guild for help with that.