I recently switched to Watchman from Combat and it's night and day in terms of how much less stressful it is to play.
Combat is chaotic and you really have to be on your toes to squeeze out the damage you want. You have to be incredibly aware and you have to have incredibly quick reflexes to adjust your prioritized attacks to fit in incredibly small windows. You almost have to be hyper aware at all times.
Watchman is much more relaxed and gathered and you really don't have to stress nearly as much. It's much more of a set rotation and there is very little you need to worry about. Set your dots, do your Merciless, wait for your Juyo stacks, wait for Zen (which you don't feel like you can even waste because it's almost always up, unlike Combat) and do it all over again for greater damage. This is just in my experience and YMMV.
In my opinion, Combat is much more satisfying and a greater challenge than Watchman, it's just too bad it's not as viable at this point. I do miss it greatly.