Owning your own home

I live in a not dissimilar sort of house (not in Bristol), with some not dissimilar problems...many of which were not diagnosed or picked up i the survey when I bought.
It seems like you've gone into this with your eyes open but absolutely don't under-estimate the amount of work/money that goes into making some of these things good (I naively did and it's been stressful at times).
Also try not to let yourself get rushed by anybody during the process. Do things in your own time and make sure you feel as comfortable as you reasonably can (obviously the whole purchase process is one long squeaky bum time). By all means chuck in an offer you're comfortable with to get your foot in the door but following that try to keep your own needs first and foremost.
I got bullied by sellers/solicitors a bit (in hidsight I think they took advantage of my good nature and FTB naiveity) and I would encourage you to be strong and make peace with feeling confident to walk away if you start having nagging feelings.

Like others have said it's got bags of potential and I wish you the very best :)
Not sure if I cna help more but feel free to PM me if you wish