If you have experience riding on gravel road then you know what to expect. I have experience on gravel roads but choose avoid them with FJR. Just my choice, not a limitation of the bike. I have road the FJR on gravel roads and don't enjoy it.
Carrying a lot of gear on the FJR generally means putting stuff on the rear seat. It is like having a passenger on the bike without legs. Steering becomes heavier with all the weight up high. With the FJR I stay at hotels. When on my DR650 in the woods I will camp cause hotels may not be available, plus if I break down, I am prepared for a few nights in the woods.
Try the FJR on a gravel road or two without gear, then if you like it, return with gear and try it. It doesn't matter what we out here think, it is a matter of how you want to spend your free time.
Best wishes.