I don't do dirt and gravel. I use my DL1000 on pavement 98 percent of the time. I don't like chains or chain maintenance. Been happily riding shafties for the last 20 years.
But, I didn't let that stop me from buying the DL1000. I don't get too carried away with chain maintenance either. I lube it once in awhile. I cleaned it once. I adjusted it once (a very small amount). I have 7500 miles on it now. If my chain wears out a couple of thousand miles earlier than it would if I took better care of it - so be it. I bought the bike to ride - not as a chain maintenance exercise.
I don't think I'd spend the money on the belt drive conversion though. There are better ways to spend money on this bike. Luggage, centerstand, aftermarket seat, nicer mirrors, better windscreen, case guards, suspension upgrades, better tires, etc. would all fall higher on my wish list than a belt drive conversion. It's not that the bike needs all of that right away, but each thing you do over time makes it a nicer ride.