QB (1) - Drew Pyne
RB (1-2) - Chris Tyree, Seth McGowan, Reggie Love
WR (2-3) - Jordan Johnson, AJ Henning, Jalen McMillan, John Humphreys, Daniel Jackson, Maliq Carr
TE (2) - Michael Mayer, Kevin Bauman
OL (1-2) - Paris Johnson, Andrew Raym, Bryn Tucker, Kevin Pyne, Andrew Gentry, Peter Skoronski, Jimmy Christ, Tosh Baker
DL (4-6) - Arik Gilbert, Darrion Henry, Rylie Mills, Cole Brevard, Xavier Carlton, Aidan Keanaaina, Braiden McGregor, Jalen Logan-Redding, Alex Ehrensberger
LB (1-2) - Sav'ell Smalls, Kalel Mullings, Curtis Jacobs, Jaheim Thomas, Cody Simon
DB (4-5) - RJ Mickens, Clark Phillips III, Kristian Story, Enzo Jennings, Darius Snow, Makari Paige, Lathan Ransom, Jalen Kimber
Disclaimer: I listed prospects at different position groups who have interest in ND, have visited a few times, or the staff has been out to see in the last few weeks of the recruiting period. I'm not guessing they come to ND, but rather pointing out some potential fits at those positions.
QB is obvious so I'd start with RB in looking at the roster for 2020. The way I see it is ND probably has room for 4-5 RB/WR's in the class. They don't lose a single RB to graduation so they'll have 6 RB's on scholarship in 2020 which is a lot to take 2 pure RB recruits in addition to those 6. I think the staff would love to add a top RB and then an AJ Henning-type of player who could play both and has positional versatility. Dream scenario would be getting Chris Tyree & AJ Henning and then two more top receivers to go along with it.
OL returns 15 scholarship guys and maybe 14 if Darnell Ewell is moved back to DLine. In terms of numbers, ND wouldn't need to take more than 1-2 guys out of necessity but I do think when all is said and done, they might take 2-3 guys because they are in it with a lot of talented dudes. I think off the bat the prize would be Paris Johnson Jr and Matt Freeman seemed to confirm they snuck him on campus in December for an unofficial and its clear that Jeff Quinn would love to flip him if possible. From there, ND has gotten every single guy I listed above to visit except for Jimmy Christ who I expect to visit in the spring at some point so they are looking pretty good at the position.
DL loses Khalid Kareem, Daelin Hayes, Julian Okwara, and Jamir Jones so they'll need somewhere between 4-6 guys. There are a lot of different variables at play with the DLine which include Ovie Oghuofo moving to Drop potentially, rumors of Jamir Jones taking a 4 games played redshirt in 2019 so he could be a two deep player in 2020, Isaiah Foskey maybe joining the squad, and Darnell Ewell moving back to DT potentially. As for the targets, I'd say that the 3 biggest by a pretty wide margin are Rylie Mills, Braiden McGregor, and Aidan Keanaaina. That's not to say ND isn't heavily recruiting Arik Gilbert, Darrion Henry, or Jalen Logan-Redding, but they seem to be going all out for the top 3 right now and the interest seems mutual from the top 3 (Jalen Logan-Redding also seems very very interested). The dream start to the DLine class would be the top 3 guys committing soon and then they can work on adding some other stars to the ranks. Once again, Elston has ND in position to do some really nice things on the trail in regards to DLine recruiting.
The Linebacker corps returns everyone except Asmar Bilal in the 2020 season so the numbers should be real small in terms of needs. I'd guess 1-2 because Asa Turner may show up and Ovie Oghuofo may or may not move to DLine. Todd Lyght has been out to the state of Washington twice in recent weeks to go big game hunting with Sav'ell Smalls. Smalls would be a gamebreaking addition to the roster, but I wouldn't consider the interest real until the kid comes across the country to visit. Kalel Mullings has essentially a two horse race between Michigan & Notre Dame with Michigan presumably on top right now. Al Washington, one of his recruiters (Don Brown is his primary recruiter I believe), just left Michigan so we'll see if that allows ND to make a move because he'd be a great add. Also, Jaheim Thomas is picking up steam in his recruitment, but he might be a Drop candidate and not a LBer. Lastly, but maybe most importantly, Cody Simon is an obvious candidate for a LBer spot because he comes from a great bloodline and has obvious ties to ND.
At Defensive Back, ND has recruited incredibly well over the last two classes and hopefully that continues with the 2020 cycle. ND loses Troy Pride Jr, Donte Vaughn, Jalen Elliott, Devin Studstill, maybe Shaun Crawford (eligible for 6th year), and maybe Alohi Gilman (5th year vs. NFL draft). This is a position group where they'll actually need a solid amount of numbers in this cycle. Thankfully, due to the work of Terry Joseph and Todd Lyght, they are in great shape with a bunch of different guys. RJ Mickens mentioned in a December interview he got a visit from Todd Lyght and wanted to return for a third visit to ND. Clark Phillips III has loads of interest in ND and hopefully makes it to ND in the spring (if he does, look out). Kristian Story surprisingly made it to ND in the fall and loved his visit. He got a visit from Terry Joseph last week and might return this spring which is huge coming from a talented Alabama native! Enzo Jennings might be the best bet for commitment of any of those guys listed above because he's visited Notre Dame multiple times and has raved about the school. Darius Snow seems to be a Michigan State lean, but he's just said he's coming to the February junior day which is great news. Lathan Ransom also confirmed his plans to visit ND for the February junior day. Jalen Kimber is another prospect to look out for out of Texas.
All in all, ND is in great shape with a lot of position groups and I think fans should be really excited about what the class might look like. This spring will give us a lot of answers as to the direction that this class is going. My guess on class size would be 21-23 guys right now. That could grow, but looks to me like a smaller class is in order for now.