> so the idea is to make each piece of clothing a different bodysuit and texture them individually?

you can do that if you'd like, i would experiment with the various templates and see what works/doesn't work, they all have various sliders to fit different effects. Erasing portions of the bodysuit would let some clothing fit when it would otherwise clip. Assuming your avatar is your fantroll, you will probably would want a bodysuit for your top (for the tight fit), for example. but you might want a skirt for your OC! You so you the skirt templates in the bottom section, or even the long coat in the top section or dresses in the dress section. They all have different editable parameters and degrees of customization, the chubby bodysuit might require some creativity on how to make it work. (i.e. you'll need to Experiment).

> are there any masks for the textures so i can work with them in another app?

if you right click a layer and click "export guide", it'll make a give you the mask for that specific template. You can then bring it back into vroid by either hitting the image icon next to the plus sign or by right clicking a layer and hitting "import".

> this is a sign sent down from the heavens....... i must vroid more............

i really want to see some fantrolls in Sahcon's VRChat meetup! There are a lot of canon characters but it's really cool to see things people made from scratch, esp when its relatively accessible if you can already draw. So yes, you should vroid more.