Sounds like you may have picked up some contaminated fuel and this is filling the canister with water content
I would get this attended to sooner than later but not sure if you can reach below the filter to drain it down yourself?
Sometimes if the front brake pads have been replaced at some point in time then worth checking that the pad(s) not moving due to part of the fitting kit missing
Unless you can get the alignment altered to compensate for the UK camber and bias it slightly over one way?
Otherwise, tyres may make a difference possibly?
Halford always have a good stock and may be able to order one or even have something similar to fit as they just stick over the old broken mirror glass
I would take each component off individually and inspect then reassemble and see if that produces any results
Time consuming but I'm sure you'll find a defect somewhere in there
You sure it is not the wiring coming through from the roof to the tailgate that is broken
Pull back the rubber boot that is surrounding the wiring and check the wires
Some tyres can make a horrendous noise but it may also be the tyre profile that is picking up and transmitting more noise (e.g. lower profile tyres)
Only way to determine is when you need new tyres you can search by noise ratings and try to find the lowest
A quick eBay search is showing some rails but mainly cross bars
https://www.ebay.co.uk/sch/i.html?_from=R40&_nkw=2004+honda+accord+roof+rails&_sacat=131090&LH_TitleDesc=0&rt=nc&Type=Roof%20Rail&_dcat=33651
Rubbing back the affected area and filling possibly?
As long as it is not within a certain distance from a structural part of the car and is not too large then this repair should be acceptable
My main concern in what you have described is the high pitch wining noise .... this could be an indicator of the problem
Do you know roughly where the noise is coming from?
I would be tempted to fit a secondhand lock and key but will require two keys to be used for the vehicle
Otherwise would be a shame to get shot of it for a simple (and low cost) repair