HoHun, Vermillion,
Keep in mind that service ceilings aren't hard ceilings.
The example that Verm mentioned, the Lanc, perfectly illistrates this. The RAF considered an aircraft's operational ceiling to be the point were its rate of climb dropped below 500ft per minute. The aircraft could climb higher, it just took an inordanant amount of time.
There are examples of RAF aircraft exceeding their operational ceilings during WWII and in AH there is nothing stopping anybody from accepting the Lanc's climb rate of less tha 500ft per minute and taking it higher. Indeed that is what has happened everytime you see a Lanc above 20 odd thousand feet.
I would not be at all surprised if the USAAF and Luftwaffe viewed operational ceilings in a similar manner to the RAF.
If that were the case, and I think it likely, the He177 would hardly be limited to low alt operations.
A second point is that while "strato buffs" are a popular whine topic, they actually account for a rather small percentage of buff flights in AH. The vast majority of buffs (B-17s, Lancs, Ju88s and B-26s) that I have seen have been 25,000ft or lower.
Staga,
The He177 is much, much smaller than the B-29 and, if that image is at all accurate, the pilot is sitting much closer to the windscreen than in the B-29. The B-29 I imagine is more of a control deck out of some 30s fantasy aircraft.
Besides, don't you want the challenge of flying a prop plane that has a wing loading of 80lbs per square foot? We're talking about an aircraft with a take off weight of 124,000lbs. The Lancaster and He177 had a take off weight of 68,000lbs, the B-24 a take off weight of 60,000lbs.
Each of the B-29's engine nacelles was the size of a P-47. The sheer size of the B-29 would be impressive.
The B-29 was also produced in the thousands and saw heavy combat. The B-29 is in all ways a valid addition, I just cringe at how much work that Superfly and/or Natedog would have on their plate if HTC does the B-29.