How much rust is too much?

Here's what I would NOT do if I were you. I would NOT let a poll on an internet forum with a bunch of votes from OTHER folks make your mind up about it. Do what YOU wanna do with it. As mentioned, much worse cars have been fixed. It'a all about how much work YOU can do or PAY FOR, not what somebody else thinks.
You have a habit of getting in the way of (people not as smart as you think you are), working on their own cars.