I think most ppl know Snow's plan to have three scoring lines, and a gritty third line that can at times be broken up and mixed in amongst the top nine scoring forwards when playing certain teams will certainly help.
I've been thinking about this for a while now. Based on the past, a little Isles history, and personal theory of observation, this is my guess at the secret master plan Snow is using to rebuild Isles defense. Rather than a simple top four D and bottom two D, I believe Snow's plan is much more evolved than he has been given credit.
To start, I have not designated any pairing 1st, 2nd, or 3rd. Each is a different weapon to be used by the coach at the right time. For sake of explanation, I've used (A), (B) and (C) [had to use something to get point across].
The top six D are broken down into role/skill set players - each role/skill set has the list of depth prospects who may or pay not pan out. All D men have to be able to make the first pass and have some skating ability. As we can see, some roles/skillsets have depth while others lack:
Amac - Hamonic
Streit - Hillen (depth prospects - DeHaan, Donovan, Katic, Ness)
Wishart - [Big right physical D, not in system] - fill-in vets: Martinek, Gervais, Jurcina
(depth - (depth prospects - DeHart, Kessel, Klementyev)
*Note: Wishart is still a prospect.
Eaton is at bottom of depth list as a bridge to future player. Buyout Mottau.
Amac and Ham have been listed as (A) just to simplify the process. While Wishart is still a propspect, he has excellent potential, if he can correct the defensive gaffs he has every so many games, he may own a top 6 job and be the left side (C) pairing - the big left D. If not, a good team will take advantage in the playoffs, and a few gaffs there can end a cup drive (ask Steve Smith). If Wishart pans out, no reason he cannot play with Hamonic and Amac moved to (C) pairing now and then. Hamonic looks like the real deal. No telling how far he evolves. If we ever find our missing Big right D, we may have 1 and 1a at this position, which I believe is the plan.
The missing big right D - Most pray for some Draft lottery love (we might not even have a shot that way) and Adam Larsson, some want Isles to draft Dougie Hamilton if no Larsson available - while at this point Hamilton is more probable than Larrson, both are hypotheticals. Isles do have a bit of prospect depth for this role/skillset, but that depth is long shot prospects. There are no highend prospects like B pairing. This area will therefore, most likely continue to be filled by vets Jurcina, Gervais and Martinek, unless an upgrade is made. While all three have issues, a simple look at the number of NHL games played demonstrates Isles will need them if Snow cannot find an upgrade that would be the right fit. Jurcina is helpful when healthy, Gervais, though soft, is better defensively as a number 6 defenseman as opposed to being used as a top four. Martinek is injury prone, but even if he plays around 35-40 games - he's done that this year - Martinek is a good teacher and would help babysit and teach one of the kids.
The last part of my theory, (B) pairing: The Isles are trying to build a duo left D pairing, with above average NHL speed and passing to compliment their three forward scoring lines and other two defensive pairings. Streit fits this to a tee and is one of best in league. Hillen is the best of the prospects at the NHL level at this time. He also has only played 160 NHL games. While he has not taken the spot and owned it, he has shown flashes. Nonetheless, barring an upgrade or a prospect breakout, Hillen is currently second in depth at this role/skillset - however, this is the role/skillset where Isles have most prospect depth.