Body type in cosplay is a huge issue. It’s one of those things that is highly contested in this world. Is cosplay okay for someone who isn’t exactly made for the stick-thin character models in anime?
Yes. It is.
Proportions are super important for creating something that’s going to be flattering for your shape. I’d highly recommend a read of this article here to understand it a little more.
If you’re making something with your own design, understanding these things are pretty much going to make or break a costume peace. So get out a measuring tape.
If you have a dress form that actually fits your shape then that’s excellent, and will likely make it easier with your measuring for these proportions.