OK, here's some perspectives with back-of-the-envelope salary cap math (not using my kids' new common core curriculum, which would result in every answer being "42").
Paying LT money for an OG is silly...the Ravens were wise to let KO walk. As for Wagner, Juice and Williams, the Ravens could "afford" to pay to keep all three, but the opportunity cost would be an inability to sign players for depth at other positions (ILB, OG, C, WR, DB/FS). The Ravens currently have about $15M in cap space. Assuming they make a reasonable set of cuts (Watson/Pitta, Doom, Wright, Lewis, maybe Webb, Zuttah, etc.) that would push the number up to about $25M net of dead money.
Ozzie wisely likes to plug holes in the roster in free agency ahead of the draft. The market price to keep Wager (est. $7M), Williams ($11M - your estimate) and Juice (est. $2.5M) would be over $20M. That would leave a scant $5M to plug holes at RT/G (depending on where you slot Alex Lewis), center ($1.5M), ILB ($1M), CB ($2M), Edge ($4M) and FS ($1.5M). Also, don't forget that we will need to sign a backup QB ($2M). That's about $12M in needs.
If you believe in Alex Lewis at RT, and Pierce at NG, and that finding quality blocking FB (albeit without Juice's ability to catch the 3-yarder in the flat route) is fairly easy, the Ravens should invest the bulk of their notional $25M cap space in an edge rusher, defensive backfield, ILB and interior O-Line (in that order) in my opinion. Pay for playmaker positions, and fill-in/draft/develop the rest. RT, NG, and FB aren't playmaker positions. Besides, we'll get comp picks to replenish those guys that were drafted in the mid rounds anyway.
Yes your agreement is appreciated, However I didnt say keep Wagner. So adding the average 6 Mil to the 5 mil as you said leaves 11 mil which is near the 12 million we agree is about the "relative" cap space using the players example above. The original post mentioned getting rid of al 3, I said keep Williams and Juice if they will sign at the amounts discussed, hopefully a little lower. Its all a money game, I would focus on Williams. Thats my opinion. Some say focus on Wagner and let Williams go. Its a roll of the dice really, it is going to be proven on the field. I guess my biggest logic is that with Yanda, Stanley, Jenson, and Lewis I feel the O-line is anchored for the next 2-3 years. adding the young talent which by the way the Ravens added 2 young O-line members in the offseason. The D-line without Williams would rest on 3 year Jernigan, 2 two year Urban, Davis, and 2 one year Pierce and Henry. and if signed Hurst and Guy which if both kept might cost as much as Williams. I think that is the hold out right now. The Ravens cannot afford to let Guy and Hurst go if Williams doesn't sign. Personally I think the one player that the Ravens should pass on is Zuttah. I think he has trouble in the Ravens scheme. If I were the FO, I would save money at Center and pick up a top Rookie at #2. That's my plan for now and I'm sticking to it. But of course I don't make the decisions, and some might not like that decision.