No.
To the ones that it would make a big difference, probably all of them are chiming in here on this post, to the 1,000s of potential buyers these small things will not matter, and to a new RVer it will mean nothing to them since they have never had to replace trailer tires or brakes, which are wear-n-tear items anyway.
Two identical campers, same price used; one has 4 brand new Endurance tires, one has worn out walmark tires. Which one gets bought? The one closest to home, or the one with prettier pictures.
Some upgrades like solar, or other huge additions, would only matter to a person thinking of wanting that upgrade anyway, to others it means nothing and adds no value. Having a TV already in there ($100 - $200 value) would mean more than other upgrades that only a seasoned RVer would appreciate, as I observe many want a TV.
Fix things that are broken and make RV ready to go camping, but upgrades are a bad idea for selling. Actually, undo the upgrades and keep them for the next RV as this will ultimately save you money, or you could lower the price by that amount. People do not want your upgrades, well, except for tires...
As far as brakes.... "What's a brake controller?" is what you will hear.