I suppose it depends on skating habits to a great degree. I end up wiping water off of the bottoms and sides of my boots after each skating session - snow spray ends up melting on the boot surface, especially all over the sole.
Do your skates have natural unfinished leather soles from the factory? If they come with lacquer or paint or some such, then it should be repaired using lacquer or paint or something that matches what they came with. I think it's even more important to use a sealant between the boots and blades.
Raw leather soles take more maintenance to keep nice, but the advantage is that with proper care, it's easy to keep them nice, and they look phenomenal. I have painted soles now and am not sure what sort of paint is appropriate to use to touch them up. If I were to use Sno-Seal as a preventative measure, it would prevent any new paint from sticking in the future. Son-Seal can be re-applied any time and protect any area that's worn thin. When you damage or wear down the paint, it's a vulnerable area, which again could probably be mended with a bit of paint. You could apply your own epoxy coating, but it too will end up damaged and needing repair. I would be very hesitant to do that, because it would be difficult to ever remove and I doubt it would look very nice.
This is how my painted soles looked after about a year of use with no Sno-Seal...not exactly "good":
Not a great-quality picture, but this is what they looked like new:
It's hard to see in that picture, but the soles were actually quite water-damaged underneath and around where the blades attached - you can see dark areas around the sole plates. The metal would get really cold on the ice and even when dried would attract some amount of humidity. Plus the fitter did not use any sealant between the boots and blades, so water would end up trapped in there.
My more recent boots were done by a better fitter who used a silicon sealant between the boot and the blade, which is invaluable. However it too should be periodically replaced by removing the blade, peeling it off, and applying it anew, as the boot will settle onto the blade a bit over time.