I'm curious if people really think the slot receiver is going to matter that much in MLF's offense? He doesn't strike me as a 3 WR set guy, his history with the Titans and his statements appear to indicate he wants to run more of a 2RB/1TE/2WR or 1RB/2TE/2WR offense. For reference, in 2018 (when MLF was offensive coordinator), the Titans had 2 receivers with over 750 snaps and the third had a grand total of 178 offensive snaps.
Actually, the 2018 Titans had only one WR with over 750 offensive snaps and the third most was 444, but no matter, total WR snap counts are shown below.
2018 Titans: 245%, averaging 3-wide on 45% of snaps
2019 Packers: 254%, averaging 3-wide on 54% of plays
That difference in a 62 play game is about 6 snaps. I'd say that would be around the max you'll see of the reduction in Packer 3-WR sets this year vs. last.
Of course the Titans had Mariotta throwing to Corey Davis (2nd. season), Taywan Taylor (meh) and Tajae Sharpe (also meh), so you might want to adjust that 6 snaps down a bit.
You wouldn't expect a WR to top a 90% snap count in a healthy season. Adams has never reached that number and over 80% only twice. If you get lucky and your top two go 85% and 85%, there's a 75% WR snap count out there for one or more guys if that Titan number is matched. If your thought is that the question marks at WR are mitigated by not putting many of them on the field, I think you'll be surprised at how small the difference might be over last season. Whoever the top two might prove to be, one or the other or both are likely to miss games. It could be 85-60-60-40.
Really, it comes down to where the talent shows up and what works. You run what is working and that usually means you put as many productive and playmaking guys on the field as possible. It will largely come down to how the TEs show up. If a TE runs out of the slot with another guy in-line, it's a distinction without much difference given the leading slot candidates are big slots, not ankle breakers.
Regardless, I'd be pretty surprised if 2-Back is at all a staple. If Deguara is any good as a FB, it might be with Kuhn-type frequency, 10 or 12 snaps a game against some opponents, less against others, more if burning clock in the 4th. quarter, less if trailing. I still don't understand why people persist in refering to FBs as RBs in this day and age when FBs rarely carry the ball.
If by 2RB you mean Jones and Dillon on the field at the same time, I doubt you'll see that very much. The Jones/Williams combo was pretty rare last season. Jones and Ervin? Well, we saw a very little bit of that last season with Ervin split wide and I'd expect a very little bit of it this year. Ervin may get more carries on end arounds than he'll see targets.
The biggest variable isn't some preconceived notion of philosophy and personnel. It's how well the defense plays. Field a top 5 defense that keeps points off the beoard and you are afforded the luxury of running the ball more. Fall behind and you'll need speed on the field.