WW-I is a difficult act to pull off, and never ends up working out very well in a MMOL flight sim. There are several factors that work strongly against it.
Planes of that era are inhearently unstable, and not easy to fly. Induced yaw is a pain in the butt to fly with. They have tourque that twists the planes into the ground because the weight of the engine is 90% of the total plane weight. Spins and departures are commonplace for new pilots and so a great number get discouraged and never come back.....moreso than we have now in WWII.
There is a complete lack of parity in WWI planes. The gap between planes is huge of the course of the war, and was not at all equal at any given timeframe. Unless you use a rolling plane set, and specifically try and match 2 or 3 planes for each side (ignoring historical timelines) you get a 40 plane set that has 3 or 4 planes flown exclusively (imagine a MA with a few dozzen planes like the P40 or Hurrican mk1, plus F4u 1D, La7 and Spit MX 9......everyone would fly the few top planes and nothing else.
Any simulation worth a crap has to account for the terrible guns most planes had, along with the relativle soft nature of the target. It took lots of hits to do damage, and almost any damage was fatal as the structure or its areodynamics has very little to give without failure. TO score hits you have to be VERY close, and in the word of internet lag, that doesnt work too well. Collisions would be rampant and you would have to have them on to be at all realistic.....the whines would be endless.
Finally the planes are SLOW...and I mean Yugo, moped slow. Many of them barely cleared 100 mph (many didnt). Relative distances between airfields would therefore also need to be short as a fleas....personal appendage:D . RIght now theres 25-35 miles between many bases....in a WWI sim to maintain a similar 'drive time' youd need 5-10 miles......it looks silly when you can see the enemy taking off from his base as you take off.
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Its not that it cant be done, its just more difficult than you may imagine converting into WWI.
