Yes, they're all aluminum, but the detailed hilts can sometimes be more difficult and/or less comfortable in the hands for certain purposes. Apprentice is a good one though, sounds like you're just building up the standard callouses that develop in swordsmanship. If you're concerned, you could always post a video of your spinning, which would help me understand better if you're doing something wrong.
No I don't think I'm doing anything wrong. I guess lightsaber twirling & swinging is an intellectual thing involving callus buildup, pretty much like how fingertip calluses buildup when playing guitar the first time.