There is lots of info under the technical heading and its subdirectories. I do own a copy of the Complete Encyclopedia of World Aircraft. Its a good book although a bit heavy.
The big problem with creating a data base of this magnitude would be accuracy. Especially when you get to sub models of some aircraft. For example look at the Bf-109. There are so many sub models that each one has some thing that is different whether it be speed, engine, weapons and such.
Then there is sources. Depending on the source you use which one is considered accurate. Like you said. Its easier said then done.
Thanks though for the thought!!! Keep it up, always looking for idea's.