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You make good points, so I'm not going to delve too much into the whole list. I just wish to clarify two specifics on which we don't seem to see eye-to-eye: Dunno about the Mk.41 SD not being used by anyone, both the Aussie ANZAC MEKOs and upgraded Adelaide/OHPs are listed by Jane's with a Mk.41 mod.5 for 8 NSSMs or 32 ESSMs, for instance. In any case, what I had in mind was the Mk.48 (PDF warning), either on-deck as on the Murasame or City (Canada) classes or grafted on bulkheads as on the modernized Karel Doorman. Both versions minimize the structural impact compared to a Mk.41.
But again, the question mostly makes sense if your design veers towards a more modular approach with stackable VLS blocks. If all your VLS cells are built-in, of course it is necessary to have some strike length in there for mission payload. But if you're ready to resurrect the NTACMS, you're so far away from an off-the-shelf design that you might as well go for a tactical-length Mk.41
Granted, there is a risk of mission creep, but also a major plus when seen only from a logistics angle. Keep in mind that a lot of countries with limited ship-to-shore infrastructure use landing craft without the least warlike intent simply to service their more unequipped shores. As soon as ship-to-shore logistics happen (and they will), your costs and transfer rates will be abysmal if you rely only on helicopters.
A dry well deck with a small ramp for RHIBs and Griffon-class hovercrafts, and/or a mobile RO/RO ramp to load LCUs bow-to-stern at low speeds, are both good compromises IMO.

Also re. azipods, I don't know about the USN criteria, but outside of the USN, at least the French Mistral and Spanish Juan Carlos/Canberra LHDs rely on pods while fully militarized.

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You're definitely right about the Aussie Perry mods, at least. Not sure on the others. Mea culpa. I'm in the process of packing up to move and won't be looking much at this right now, but in a week or so I might look at something less impactful. Or I might bow and scrape and pay homage to the God of Commonality and stick with strike-length anyway.

Aft, what I was envisioning was something on the scale of the stern gate on the Newport News LSTs, able to mate with (but not berth) an LCU or similar. I definitely do not intend to be limited to exclusively helos for logistics, although I sort of like the idea of basing CMV-22B (the formalized COD Osprey) on these large amphibious decks.

On the logistics side it really is hard to avoid mission creep, because I have way more hull volume than I can reasonably exploit. Steel is cheap, as they say, and I must not fall into the usual cycle of feeling the need to use every inch of deck space and every ton of buoyancy to pack expensive electronics or complex handling systems. I might make a concession of a high-ceilinged main deck that would allow a large, open center bay with a gantry crane to handle 20' containers, with passageways and whatnot on either beam... we'll see.

Good point on the Mistrals. I'll rethink that part of the configuration, because I really do like azipods at these non-fleet speeds (although Mistral herself is a little too slow for me, I really care about the 20 knot floor for USN amphibious groups).

The dutch Johan de Witt has a 19.5 knots speed on diesel-electric thrusters, not certain if those are azimuths or azipods.

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19.5 clean on trials is not shabby at all, but in combined operations the USN has required 20 real knots from its amphibious ships for fifty years. LPD-17 claims 22 knots full-out, and that's sort of my baseline.

I am not certain if that is its fleet speed or it's trials speed, but the yard says 18 so I expect that is its real speed. agreed.

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Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
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A few other things I might be playing with:

• Looking at the beam to see if I could arrange AGS en echelon. If I could have three compartments each with two AGS, it would be pretty funny if I had more fire support on a single hull as the USN will have on the entire Zumwalt class.
• If I could do that, I could probably move everything forward and have bigger hangars/more flight deck, maybe for permanently installed Scan Eagle catapults or similar...? There are also some interesting amphibious drones that are being investigated by some companies. Those might be a good choice, since they can be larger, with longer endurance. Something I'm looking into.
• Looking at the I-Mast-like thing that will be on my ~6000 ton frigates (if I ever get around to drawing those...), and seeing if it would make more sense to install one of those, albeit with fewer AMDR-S panels installed. Again, commonality is good, and while I don't need frigate-class radar on this hull, I do need at least frigate-class datalinking and CEC. We live life over the horizon in all combat scenarios.
• Looking at azipods and stuff, again.

@Erik_t
While I don't offer much in terms of "technical" comments/advice, I always hold in high regard Your personal designs, as very interesting, imaginative and well executed.

FWIW the Juan Carlos I LHD (BPE) is listed by Jane's at 21kt, with dual-screw Schottel pods.
Figures suggest that the Mistral is comparatively underpowered, with 19040hp on-shaft(?) against 29500hp for the Juan Carlos with a CODAGE plant behind.
Means that an azipod propulsion can breach 20kt, right?

About the AGS, doesn't the beam allow you to stack two lines of AGS side-by-side without staggering? I assume that most long-range firing will happen at high elevations where the gun tubes won't collide when firing broadside.

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Soviet Century/Cold War 2020 Alternate Universe: Soviet and other Cold War designs 1990-2020.
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FYI, Azipod and Azimuth thruster means the same thing. Azipod .is just the trademark used by ABB for their thrusters

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Source Materiel is always welcome.

As far as I know, azipods are units where the (electrical) engine is in the thruster itself. Azimuth has the engines in the hull, with an shaft going into the thrusters with gearing changing that shafts orientation to that of the propeller(s).

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Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
Shipbucket Wiki admin