The wet passenger footwell is likely to be an incorrectly fitted pollen filter/trim cover in front of it missing, or as you say, full of leaves behind the rain tray. It'd be worth checking for damp in there, your ECU is in there too!!
The boot handle will be corrosion so it'll need removing, respraying etc
The original mats are no longer stocked but there are plenty of other after market options out there.
I think I may have a spare back shelf, postage would be a killer though, its twice as heavy as the one in my mk5 Golf
Not sure how to revive the door cards, I'd like to do that too



