Given your user name, it's no surprise you have a fondness for the French!

I agree about the MS.406 and 410, since this was arguably the best Finnish early war fighter. There should be both Finnish and French cockpits. The Mörkö was only built as a prototype series, so isn't that important to have it flyable.

There was a D.520 in the works by a 3rd party modder, but I think that project failed. Despite that, the D.520 would be a nice addition to the game since in addition to being France's best fighter in 1940, it was used in combat by several Axis countries in the Middle East and on the Eastern Front.

+1 for your other suggestions. A flyable Blenheim would aid both the Finns and the early War British line-up, while a flyable Swordfish would be very useful for North African and Malta maps.

There is a gorgeous-looking Sunderland Mk I which has recently been released as a mod. Polygon count is probably way to high to ever allow it to be "official" and there might be other problems, but it sure looks great!

There are two modded D.520 versions (C1 and S) available in WAW#20. The one has no working cockpit instruments, but the other seemed to me fine when I briefly picked it up for a test flight. And the D.520 is a beautiful plane...

I think that the developer of the D.520 didn't want to play by TD's rules regarding polygon count and released at least one variant of the plane as a mod.

Sad, because it would be wonderful to have the D.520 as an "official" plane.

+1 for the retexturing/rebuilding of existing cockpits over bringing in yet moar planes. The new pits for the Polikarpovs are great. The 109s and MiG-3s in particular are long overdue for an interior makeover and, for latter, exterior makeover as well.

An unbelievable amount of planes is in the game already, many of which I still haven't flown despite more than a decade of playing the game. Would rather see what is already there be further refined than to cram in more stuff.

If anything is going to be added, what the game could really benefit from is more ship types, especially the conspicuously absent Pacific types.

XB-44/B-29D and C-54
 

What do you think about these 2 airplanes? b-29d flew in may 1945 and was known as b-50, and c-54 was in use from 1942

Four questions we should ask ourselves when requesting a particular plane:

1) Was a particular plane built in significant numbers during the WW2 era?

2) Did a particular plane see combat to any great degree during the WW2 era?

3) Was a particular plane critical to a particular country's war effort?

4) Could a particular plane's role be more or less filled in a given scenario by another plane currently in the IL2 line-up? (i.e., how "unique" is it?)

For the B-29D/B-50, the answers are No, No, No, and Yes, the B-29A.

For the C-54, the answers are Yes, No, No, and Yes, the C-47.

So, in both cases, while these aircraft are interesting and important in their own ways, they aren't good candidates to include - at least for a WW2 sim. OTOH, for a Korean War/Early Cold War sim, both of these planes would be very important.

Like it or not, there's a whole lot of very cool US hardware which should never be in IL-2, because it was never deployed in significant numbers outside the Continental US during WW2, and because by the time certain planes were introduced, the Western Allies had complete air superiority over the Axis powers.

Well, your test questions (which are very well chosen) point (with no shaking hand) to British heavies in ETO/MTO and to NG planes in PTO... ;)

B-29A is in game? I thought it was standard B-29, because it can easy lose it's wing during intercepting like B-29, B-29A had strenghtened and redesigned wing which are a lot stronger and endure. In the other hand, in-game model has four .50 HMGs in top-front turret, like B-29A. So, which plane is in game?

Technically, the game just calls the B-29 in the game the "B-29", so you're right.

B-29s were extensively modified as soon as they came off the production lines, or were modified in the field, so the 4-gun top turret could represent a later block of B-29 production.

One of the small changes to IL2 which might be easy to implement, would be to give more detailed model information for some of the US planes. For example, what exact model and production block is the P-47 originally released in Forgotten Battles, or the B-29 originally released with Pacific Fighters?

Yes. Unless you want to expand IL2 to whole new theaters/campaigns, in which case you'd almost need entirely new games because of all the new maps and units which would be needed.