Miloh, I've tough a number of people how to fly warbirds and the three main concerns are consistent flight characteristics, easily repairable and flaps.

Your first war bird needs to be a cross between the sport planes we all have experience with and war birds. Sport planes are so easy to fly because they are so over powered and light. Well with a war bird we will not be light, but we can still over power it. Yes, I know there are people out there that taught scale speed and realism and I agree with them 100% except for new war bird fliers. New war bird fliers are used to more throttle being the answer to all problems and while you learn there are other solutions to the same problems its good to have that good old stand by, gobs of power. You say you have a lot of experience so you may already know a lot of this stuff but experience is needed in Stalls, Spin recovery, Elevator stall progression, and low speed flight. Its one thing to know how this works with a light sport plan with instantaneous response to throttle, its another to realize that the extra weight in a war bird required time to accelerate and realize the bad habits the sport plane has allowed to never come to light and thus be corrected. A war bird will find all of these if given enough time.

That leads right into repair! I recommend Top Flite models with 1.2 4cycles for power and a good set of retracts (no plastic parts), the covering should be iron on. The object here is to be able to make all your replacement parts your self but still have the option to buy them if needed. Also the 1/7 scale size is a good compromise between the better flying characteristics of the bigger models and the lower repair time of smaller models.

My favorite subject by far is flaps! A double edged sword if you understand them they are great if not you will always be afraid of them. Flaps can make the heaviest war bird fly like a trainer, of coarse tempered by the fact that it is not.

I recently purchased, built, and flew a Great Planes Stuka (you can find my write-up here on RCUniverse with a search). I'm very impressed with the plan as a first war bird it provides a very crisp stall which consists of the nose dropping (no wing panels). Its dirty flight character is very similar to most war birds. The covering need some special care and it is next county scale but it is good enough for taking out to the field once or twice a week.

Just my two cents

Good Luck

Joe