I play as a demon hunter and sorcerer and for that I have noticed some very nasty bugs. A lot of great rifts maps completely favours melee and are completely against ranged chars that necessarily needs distance to kill (a group of demon hunter atributes and habilities even explore that need for distance as much as the legendary gems for it). And that only creates problem for one type of class (ranges) and It only helps melee characters that are not troubled by any type of map. Because if they have the distance, they could just run it to get to the enemy, if they don’t, they face a lot of enemies very close if necessary (as the class is made for it) what surely doesn’t aply to ranged. Hundreds of times I am playing already on a extemely dificult level to upgrade gems and have to deal with 2 groups of elite and lot of minions at the very entrance of the freaking map and on that case it’s just a lost great rift materials. Because on that type of common situation, I could not go futher (or I would atract even more enemies) and could not go back to create a little distance (or I would just get out of the great rift). On a lot of maps (usually with walls and rooms, but noy only) a ranged char necessarily have to already be at 10 feet of the enemy to even begins to atract it and by that time you are already being hit by multiple targets (when they jump or are a little fast), what is probably the end for a non melee char because the class is not made to hold on damage, since one hit or two could easily killed. And to make things even better we have another problem.
Another bug or bad programing of the great rifts, the maps are timed and some really misunderstood genius put freaking labirinth maps to be base for it. Therefore, you have to deal with bad entrances and not only that but lots of dead ends for a timed map! And the last of all is the templar. For a melee character he is almost of no use on that type of map because you have to advance on the enemy for him (even he being the tank) and then he goes to the target. At this time, as a weak character (because of the class) you already took hits and lots of times died. Same goes when you are facing the guardian of the great rift. If you are ranged you have to be as far from the boss as possible, but the tank (the templar) stays by your side when you are a little far from the enemy (even not much far). So he is not good for anything on the matter because he only distracts the boss when you already are close enough to be hit by it, a lot of times when you are already being hit by it and dying because the char is really not made for that. All of that makes the great rift not a matter of effort or items conquered, but a matter of luck to get a particular map that could help the progress.