I guess there are two basic types of RVer. The short trip weekend warrior who maybe takw one longer trip a year. Then there is the traveler who may put up to 20,000 miles on the tires a year.
If you are the minimum use weekend warrior it is hard to justify the expense of high quality expensive tires if they are only going to sit & die of old age. If you are a traveler buying cheap tires is just asking to be stranded on the side of the road wishing you had plunked down some extra $ for high quality tires.
In addition to the three items listed for tires wear & then failure be sure to check spring U bolts. They can work loose. Worse, they may not have been tightened properly in the first place.
I discovered that one last year on a hot lonely west Texas highway. One tire shredded & blew. Opposite side was very close to doing the same thing. One U bolt missing. Every other one loose.
I am a 15-20,000 mile a year travel & have high quality tires, 18 month old BFG Commercials, which means they probably hung on a little longer before things went boom. I was unaware of it till months later but these tires were subject to a recall. Fine, but over a year later & more than 15,000 miles later the other 2 BFGs are still going strong.
Keep an eye on everything. Use the old fist between the tires measurement for approximate alignment.