More intensity.
Are all of your sets on your main lifts just a single rep short of failure (rpe9)? In other words, once you completed rep 8 on 3x8 day, would the next rep (which you obviously don't perform) be a failed rep or a big grinder? They should be, this will mean you will be needing to take adequate rest between sets. The accessory work alone will run you 20-30 minutes I believe. The main work can MAYBE get crushed in 45 minutes if you're on a role, but you're looking at least an hour if not longer.
Yes they are (more or less). My rest on main lifts is 90" and on accessory 60".
In accessory work I couple two exercises without rest, a sort:
Day 1:
Front Squat @ 80% 1RM 3x8 90" rest
Weighted Dips @ 80% 1RM 3x8 90" rest
Weighted Chinup @ 80% 1RM 3x8 90" rest
Leg extensions 3x10 --> Tricep pressdown 3x15 60"
Lying Cable Curl 3x10 --> Reverse flies 3x15 60"
In this way I finish all in 50'