I tried the 44 G-rift today and for some reason the mobs spawn in greater numbers but have ton of HP with decreased damage, kinda lame since in 2.2 it was easier for me to do 44 solo and now I struggle more.
Update:
Got a reply from Blizz:
They have more hp to compensate for a) Rift Guardians having their health nerfed (this is the biggest change), b) "trash" mobs having their damage dramatically reduced, and c) Kanai's Cube.
Overall, almost every player should see their highest solo rifts go up when 2.3 drops.