Holy cow, 09 harley! That's a lot of stuff to go wrong off the bat. I'd say you got a lemon there. Hope the new one works well for you.
As for ours, the issues have been minimal. We bought the unit in April of 2015, and lived in it full time from the first of June to the end of February. I tell people we were unintentional full-timers, while we waited for our house to sell during a PCS military move. Anyway, here's what I fixed or had done the first two years...
Replaced kitchen faucet last March after the CW tech cracked it while tightening the fittings. (Found out two months later while camping.)
Had the roof recaulked after the first year. Removed all the old factory putty that was kind of drying out, and replaced it with Dicor. (Peace of mind prior to a long storage during deployment.)
Repacked the bearings and greased the suspension. (Normal maintenance.)
Replaced the TV antenna with a King Jack. (It didn't help the poor reception in the valley we were in, but at least I no longer worry about leaving the antenna up.)
Replaced all running light bulbs with LEDs. (MUCH brighter now.)
Furnace had a bad sensor that was fixed under warranty.
Remounted a cabinet door that I accidentally tore off when extending the kitchen slide. (Always make sure the cupboard doors are latched before you pull the slides in.
Adjusted the stupid screen door over and over again without much success. Stupid thing still doesn't close right half the time.
Installed heat tape on exposed plumbing. (For winter camping during the unintentional full-timing phase.)
Adjusted the slide cables. (Normal maintenance.)
Replaced the tank sensors after they stopped working (under warranty). CW did the repair. Instead of pulling the Corplast down, they cut a bunch of holes in it. Didn't even bother to tape them up, so I put Gorilla Tape on them to seal them up. Hate that place.
I still need to fix the cheap fold-out love seat. The futon mattress straps that keep the mattress from sagging broke after a couple of months of occasional use. Keystone refused to fix it, because they said it was "normal wear." It's really a bad design that uses cheap plastic straps similar to those used to hold large boxes closed during shipping. I'm planning to cut a solid piece of Masonite to fit under the mattress sometime in the future.
We clean the inside top to bottom every time we come back from a trip. Floors get mopped or vacuumed, cabinets wiped out, fridge cleaned, tanks treated, sinks dried out (to keep mold down), etc. This has kept the interior looking and smelling like new.
As for the outside, I wash it before each trip (it's stored in a gravel lot), and rinse it down when we get home. Bugs are removed from the front prior to storing each time. It still looks shiny and new.
Prior to every trip, I check over every inch of the trailer. I walk the roof, checking for loose or damaged items, check tire pressures, and make sure nothing is hanging down that shouldn't be. So far, so good!