Curious as to what you mean by this. As in, what's the percent chance that WIlliams, Maye, or Daniels become top 10 QBs? For me, it's something like Williams (40%), Maye (20%), and Daniels (20%). But it sounds like you're more optimistic about Maye & Daniels...
So I don't generally think of these things in terms of a percentage, way too many variables. What I like to do is look at the things top QBs do, look at the things these guys can do, see where they have phyiscal traits that match, have shown abilites I think match, what they need to learn and whether it's something that's easier or harder to learn (or impossible).
So I would look at it like this:
1. Generally you need to be able to provide mobility in the NFL, and there are categories:
A. Not mobile, can't escape with consistency
B, Mobile enough to escape sacks and get rid of the ball, maybe even complete the play
C. Mobile enough to create plays consistently, defense needs to account for you.
D. Legitimate running threat to the point teams gameplan differently to contain you.'
2. Running as a QB, you don't NEED it, but it provides a lot of outs for many of the top QBs.
A. Not a runner, either can't at all, or only in very select situations where there is nobody to beat.
B. Selective runner, will do it on big 3rd downs (Mahomes style) but not a real part of the offense
C. Good designed runner but not explosive, teams need to account for it, but not a focus
D. Freakish homerun threat, it's a major part of defensive meetings every week.
3. Arm strength
A. Freakshow, elite strength on and off platform, in and out of pocket.
B. Elite: either freakish in pocket only, or just below that but in and out of pocket.
C. Good on and off platform
D. Good enough on platform
E. Fringe
F: get ready to learn auto sales.
4. Anticipation
A. Throws guys open
B. Anticipation on some routes (go, Fade) but otherwise see it throw it
C. See it throw it.
5. Uses the whole field
A. Uses the whole field often (really rare in college)
B. Uses the whole field sometimes
C. Uses most of the field
D. Really weak in one or more areas (usually middle, sometimes guys who can't throw one way)
6. Placement
A. excellent on all throws.
B. Good on some types of throws all platforms
C. Good on some throws (or from certain platforms)
D. Generally poor
E. Joe Milton
Then there is a bunch of miscellaneous stuff... touch, ability to make throws under pressure, ability to play from behind, injury history, size, creativity etc.
So to me...
Caleb is QB 1 because I think he's a 1B/C, 2B/C, 3A/B (arm is just below freak strength, but off platform is amazing), 4A/B, 5B, 6B, he's got decent size, no real injury issues, ridiculously creative, great under pressure, played a whole season mostly well mostly behind.
Daniels is a 1D, 2D, 3C, 4B, 5C, 6C, size concerns, but played well under pressure and from behind. His running ability means he needs to get less out of his arm to be top 10.
Maye, 1C,2C, 3B, 4B/C, 5B, 6C.. great size, no injuries... inconsistent, struggled when he got down.
Now the 2 I have lower you mentioned:
Penix: 1A/B, 2A, 3B (rocket on platform, not really on the move), 4B/C, 5D (the middle of the field is lava), 6C... good size, lot of injury history, didn't face much pressure but wasn't great at handling it, I also don't like his touch.
Nix: 1B/C, 2B/C, 3C/D, 4C, 5C/D, 6C... okay size and injury history, didn't play behind much, also with him.... his whole offense was built around getting the ball out of his hands immediately on 1, 2 reads at most, ton of short stuff. I'm just not a believer at all.
Edit- so generally to me I see 3 guys with different skillsets, but all with a lot of positives in key areas, particularly areas that you either can't teach or are hard to teach. On the other side I see 2 guys who between them have 1 elite non-teachable trait, some physical limits that are lower than the other 3, and have a lot of areas they need major improvement in at a moderately advanced/experienced age for a prospect (Daniels does too, but... elite traits). So I think it's more likely Daniels learns a few things well than Penix or Nix learns a lot. Also just way higher floor if you run like him. Maye has age advantages, and he's to me more athletic than Penix or Nix, and has a better arm than Nix.