Thierry,
I have a similar rough out-line.
I don't see any problems with your itinerary at all.
Unless I missed it, you don't mention whether you are camping or using hotels?
Having been to the Adlerhoff in my youth, I'd not bother again. Historically it's not terribly interesting, Hitler only went once (he didn't like the lift because of his claustrophobia and never went back after the opening.
You cannot get to the lift access except by coach, you have to park and use the buses.
Many people have gone there thinking that it was the site of the Berghoff (long since destroyed).
My rough out-line is:
Plymouth-Roscoff, over to the Vosges (maybe re-visit Nazwiller-Struthoff) taking-in the SOE memorial at Valencay en route.
Mulhouse and the Schlumpf museum.
Munchen and BMW Mobile Tradition.
Dachau.
Brannau Am-Inn (the monsters birth place is still there).
Mauthausen.
On via Budapest, north through Slovakia into Poland where I want to find Sobibor and Treblinka (I have toyed with the idea of Birkenau but might take that on the fly).
On to Berlin, north to Ravensbruck and then on to the Kreigsmarine museum near Flensburg.
Back south and cross into Holland towards Mons via Arnhem and Nijmegen. Then back to Arras (visit great-uncle Percy's grave) before heading for Dieppe, on to Roscoff via Normandy and buy a Roscoff-Plymouth crossing when I get there.
I will be doing a lot more sight-seeing along the way so the doom and gloom aspects are there to fulfil my attempt to understand certain aspects of human nature a bit better.
I'm hoping that mid-June will be my starting point but the whole thing may have to be put off as I'm planning on selling my place and finding another (something I've thought about for a couple of years but this year the sale will take precedence over the travel).
I have a fairly extensive list of websites that are good sources for research, email me if you want them.
) so its probably best to allow some time out for something different, eg the Hein Gerricke shop in Berlin etc. Apart from the hotel near the Wolfs Lair, personally I wouldn't book hotels in advance - just stop where and when you fancy it. If you're really stuffed for positions PM me & I can e-mail you a Mapsource Files. 
