I am completely unconvinced there is such a crowd.
The Skeleton Crew (in AH) currently consists of 6 members, and as far as I am aware at least 5 of them have only recently signed on to AH specifically to fly WW1. We are traditionally an Allied squad, and are hoping to track down more old members with a total possible 'regroup' of maybe a dozen or so. In addition to this I know of many more non SC from the old Flying Circus mob who intend to try it, again with more to track down who may want to have a looksee.
As for the sim itself, as already stated by others HiTech knows what he's doing and almost certainly has a good plan. The success of the product depends on the market, so perhaps my 2 cents worth will help in some small way.
I can only speak for a small group, but I do know that generally we like good company (tick), an accurate flight model (provisional tick), and lashings of historical flavouring (sadly, no tick).
The provisional tick for the FM is abit unfair, mainly it's excellent; our issue with the Camel vs DR1 has been discussed elsewhere. As for the historical stuff I'm referring mainly to the three country system and the availability of all aircraft to all countries. I realise this is subjective but to us it's like watching a WW1 movie where both sides (or all three sides?) fly DR1's.
I don't know why anyone would be suprised by the discovery that a bunch of people signing on for a WW1 flight sim would want as complete an experience (i.e. virtual WW1 air combat) as possible, bar the cold wind and the fearful wounds. So anything we can get, we'll take - including observation balloons, trucks and trains to shoot at, etc. But in the absence of those it's byo fun, and the guys in the WW1 arena are always a hoot to fly with (or against)
It might be worth considering sending the new 'recruits' our way - I've seen another thread which mentions the problem of the steep learning curve in WW2, what better place to learn the ropes than WW1? Hop in, start her up and try not to rip the wings off, these guys will look after you. The more the merrier. I'm not sure what the chances are of being allowed to RTB with damage in the WW2 arena, but it happens quite alot in WW1. That type of behaviour is becoming more common, and should help encourage those new to the sim to stick around.
I can see that the majority of players in WW2 may not have much interest in WW1, but I think the two can co-exist simbiotically. I wouldn't dream of just 'popping in' to a WW2 arena (way too much stuff to sort out) but WW1 being so basic (in terms of getting into action) it should work the other way, so I think it has something to offer everyone.