If you are going to fit in a dipole, you might consider a doublet fed with twin line of some kind, rather than an 80m dipole - it could be more versatile.
I’m pondering a new wire antenna as mine had to be removed recently to facillitate a rebuild of the chimney that supported it. I’ve been using the spreadsheet linked in an earlier thread, and posted by Armin @DL6GCA. Armin’s translation, together with a bit of Google translate action clarified how to use it to calculate the length of the “legs” together with the length of feeder. (I also picked up a tip from Owen Duffy’s website to avoid copper covered steel conductors as used in many commercial ladderline feeders, as they can be very lossy at LF due to skin effect)
I have nothing in the air yet, and less room than you have to play with - but I do have high noise on 160m and 80m!
Anyway, just a thought. I’ll be interested to hear how you get on, and will update when I have something working…