it is really about the drum brake and the heat it generates, some winches use an internal brake in the drum. Which causes heat which is directly applied to the line, most of the synthetic winch lines have a critical temp point of 150-250 Degrees. Under hard usage the internal braked drum can heat up past that weakening point of the rope and then it fails because its strength is forever compromised. So you want to look for a winch with an external brake. The actual drum diameter doesn't matter as long as it is larger than the minimum bend radius of the fiber type. basically all of them are, to with stand the loads put on them.
Just for fun, winches are load rated on the first wrap, and loose approximately 10% load rating per wrap on the drum. so in reality you should use as short of a line as possibles and supplement with a winch line extension. I shoot for about 70' of line in total. you can use the remainder as an extension.