If they sign a veteran starter, as I think they should/will, then I imagine they'd probably throw a mid round rookie into the mix of Jones, Brice, and Greene, and let that group of four compete for the other spot. But you're right that signing one won't negate the need to draft one.
It probably won't negate the need to draft one, but if they do sign one, I'd not be surprised if they didn't draft a S.
From your list, I'd probably say EDGE-RG-S-WR-RT-RB-K-TE are our most important needs respectively. I'm gonna give my take on the upcoming draft and FA, given that we resign Breeland, Allison and Wilkerson, sign a quality S and from the most noteworthy potential cut candidates only cut Bulaga and Crosby.
For Edge, I'd love to see the Packers double dip at EDGE, with preferably our first pick and a 2nd-4th rounder. I'm not sold on cutting Perry yet as it is just not very efficient cap money wise. I'd rather do it next year as his cap savings would be relatively bigger (correct me if I am wrong?). Maybe after a strong draft, but right now I think he is the veteran presence we need if Matthews is walking (which he will). I got to admit I also have a little homer bias here since my nickname is Perry and I just really want his jersey if he actually has an epic year for once. Little chance though. In FA, I dont see us competing for Clowney. Smith/Fowler/Ray seem like more reasonable targets, but I think the Packers gonna come up empty handed in all of these pursuits (if they engage in any).
I think giving Aarod more peace of mind starts with a cleaner inside pocket. I'd agree with you on drafting a RG, in the 3-4 round range if it were up to me.
For S, some interesting FA options where thrown around by forum members. I too believe this is where the FO is going to aggressively pursuit a FA. Mathieu would be my preferred choice. Collins would be great too. If we do sign one, I dont mind if the Packers take one with a day 3 pick. I wouldn't enjoy another high pick thrown at the secondary, and I believe Jones + Signed FA can hold the line adequately. I also saw an article suggesting that Jackson should get some reps there. I really don't mind seeing some experiments happening at the central backend these past 4 weeks in order to really determine what we can get out of all our youngsters in the secondary.
Cobb is gone, and while Adams has shown to be a legit WR1, I am not to confident that Allison with ESB, MVS and Kumerow will be strong enough of a group. A shifty slot guy would be my preferred pick, with either our last pick of the 1st round or a day 2 pick. Also a possibility to target a FA, but I can't really think of any that would be cost-effective options. Jamison Crowder maybe?
Drafting a solid RT is paramount. I'd cut Bulaga; cutting him essentially provides enough cap space to resign Allison, Breeland and Wilkerson, solidifying 3 positional groups in the process. I'd like to see our 2nd or 3rd pick spend at RT.
J Williams is imo nothing more than a reliable back up, and adding a dynamic bruiser à la Cook/Henry would be wonderful. I wouldn't even mind drafting one higher than a WR if the right prospect slips due to the devaluation of its position. When did ATL or NO become dangerous? When they had an explosive RB duo. What better way to relieve pressure of Rodgers if we are able to consistently obtain a new set of downs by just running the ball? Even though I like A Jones a lot, I'm not confident he can be a true bell cow with 40 carries a game. I'd like to see them take a prospect in either the 2nd or 3rd. In FA, Bell would be great but we'd be outbid by the Colts or Jets. Furthermore he is somewhat similar to what we have in Jones. Ingram or Barber maybe?
K is pretty obvious, Crosby has not been producing up to the standards and it seems time to move on. A 6th rounder would hopefully do the job.
Finally, some depth at TE would be nice as well. Graham is here to stay, and I'd like to see Tonyan move up in the pecking order now that Kendricks and Lewis are gone. Taking a day 3 prospect would be my choice.
To conclude things, I'd add a cover ILB for depth. I think we are still set on the DL for one year if Wilkerson is back and, Daniels, Clark, Lowry and Adams can still ball out. CB is another group I'd still be confident in with Alexander/King/Jackson/Breeland/Williams/Brown. Maybe add a bargain FA for depth. LT LG C QB have performed well enough to not warrant any strengthening at this point.
By my (very) rough estimations, this would give the Packers ample of room to pursuit a guy like Mathieu, a good complementing offensive piece (RB, WR) while also being able to extend Clark and Martinez respectively in 2019. This would also leave space to pursuit backup depth at CB/OL. My draft would then look as following:
1a EDGE
1b RT/WR
2 WR/RT
3 RB
4a EDGE
4b RG
5 S
6a K
6b TE
7 ILB
Pretty offensively oriented, and while I know thats not ideal given that its a defense heavy draft, I feel like focussing on O is just more important this year. IF we retool correctly now we can bring back stability in the O for years to come. Furthermore, if we are able to sign a good offensive piece in FA, our remaining defensive needs in S and ILB can move up the board.
Finally, I'd like to stress that this is just my visualisation of needs in order of importance, assuming that we pretty much keep all our under contract players apart from Crosby and Bulaga, bring back relatively cheap one year stops in Allison, Wilkerson and Breeland, and sign a quality S.