>>412335374
No, plus they only have a significant impact if they're active. If you have some that you have on but never change just merge them into the basis shapekey and delete them.
>>412335145
Install blender, watch: https://youtu.be/8MkgXcidxg4?t=201 from timestamp and follow along. The goal is to cut the model down into the pieces that are visible only and make it into a state that you want to have as a default with no optional extras so don't bother keeping several outfits on a single model for an optimised version.