TBH, I like some quantity of the 'grinding', but not too much (i.e. if I had to run Azmodan 500 times before reliably getting a trophy then I would get bored). For me the tedious part comes in two scenarios:
1. You need the charm upgrade because it makes following content undoable (i.e. +max resist as wulf mentioned) -> could be mitigated by moving the 'major' portion of the upgrade to the charm itself
2. You need to repeat something menial to get to the challenging part many times (i.e. I think I spent more time running to Kabraxis than fighting kabraxis the rouhgly 45 times needed to get a trophy, or imagine another scenario where yshari sanctum set items broke after 1 use and you have to re-run spectre of hatred every time ..... gah). -> could be mitigated by careful placement of new waypoints, if possible and easy to implement. I could imagine a system where you would get access to a new waypoint close to the boss after running the boss 10 times or so, but I have no idea if possible in what I imagine to be a very difficult development environment
Also, no real 'complaint' from my side, just small ideas, in general I love median and am pushing its net promoter score higher
And on another note, I definitely miss the 8 hour gaming sessions with no other adult distractions other than having to microwave something tasty.