I keep making mittens, and then I just try to figure out which of my friends they might fit after I’m done. Would love to make something big like a sweater, but I just know my first try is not going to fit snugly on a single person on earth, and it’s too much of an investment to start making one when I know it’s going to be a disaster.
There are sizing options with sweater patterns, aren’t there? Granted, I own both XS and L shirts and they fit the same, so that’s infuriating.
I think you should have more faith in yourself. Cliché, obviously, but powering through having made a mess of it is the best way to grow your skillset, and unraveling it to figure out wtf you did wrong is free. As long as you subject yourself to the time sink that is having to make and measure swatches when you’re tackling stuff like shirts, I think it’ll come out fine. The worst shall be the purling.
There are sizing options, but there is also a lot of skill, experience, and care involved in making one that fits well. Especially attaching the arms in a good way is hard, and I don’t think I know anyone whose first sweater was not awkward. Lately I haven’t had a lot of time to knit either, but indeed, I should dare to experiment a bit more! :)