[Signman]

Joe go to 16" with E rated tires most of the headaches will go away.
Keep the cold tire pressure to the max.
Goodyear makes the best trailer tire. Some have good luck with LT tires but have heard not running trailer rated tires can award you with a ticket in some states.
I have run 15" with lots of failure. My buddy searches and runs good quality E rated 15" tires with success but he has an aluminum trailer with a tube chassis car carries basic tools and minimal spare parts.
Switched to 16" have run cheap E rated trailer tires and E rated LT tires with good results you get what you pay for.

The best have been 16" Goodyear only one tire developed belt shift on on the back axle which scrubs. Caught it before it went flat luckily. There was a vibration going down the road upon inspection found a belt shifted.
When I bought a new trailer a few years back Dan Fletcher automatically included the 16" tire option. I asked about the option and he said it was already included and did not recommend 15" tires at all.