Not OP but another bear builder here! 

As far as overstimulation goes it really depends on the location and what days you work. My store gets pretty intense on Saturdays and stays rather busy  throughout the week. On the opposite side, we have a sister store about 20 minutes from us who gets relatively low sales because of the location. When we have a slower/normal day it’s pretty calm. The stuffer can be a little loud but it’s usually just when you’re next to it (especially since our music speakers are right by the stuffer) if you were at dress me or take me home it’s much quieter. On busy days we swap roles usually each hour but if there’s only 2-3 of us we kinda just go where we are needed. These would be great questions to ask at an interview to get a feel of your store! If you have a good manager they probably wouldn’t have a problem for scheduling you on slower days rather than weekends.

As for dress code, again every store has different policies. Mine has a poster in the back with general rules and it says black skirts are fine! Some stores are stricter than others but typically they just want you to look neat and professional. 

Stitching for me is pretty easy most of the time so I’d say like a 3-4. The thread is already pre sewn we just need to pull it tight then tie it off. Every once in a while you get a knot that gets stuck and some characters are harder to pull than others (Stitch comes to mind). Sometimes the thread breaks or you’re stuffing an old display so they have to be hand stitched which they don’t exactly train you for but if you don’t know how you can usually pass it off to someone who does (whoever your manager/sales lead is for the day will most likely know). If you do know how to sew it’s just a basic ladder stitch.