Agreed on pretty much all counts.
My build is tough to get a good Trial run because I need the ramp-up of getting my Fetish Sycophants passive going. Usually I get about GR18 out of the trial. Can usually smash through that quick enough to move up a few levels after.
My last one I did yesterday was GR23 and I had the boss at about 10% with 3 seconds to go. Just missed passing it. I think I could easily do it. I do hate the sparsity of mobs in some GRs, that's why I have the Fierce Loyalty passive on my WD (+30% move speed when you have any pets out, while out of combat). Really cuts down on that downtime in empty rift levels. Plus if you die it helps with the corpse runs
My goal this week is to try to get up to GR28 or so.