If I had to choose, I would say the Eindecker is my favourite aircraft of all the WWI era.
It was a monoplane, which later became the template for most aircraft, up to the biggest airliners of today. The gun/prop synchronising revolutionised air battles, and despite the later WWI aircraft being much more advanced, this type in my opinion is the most iconic of the whole war. Plus, it has a relative simplicity in design and construction.
If I were ever to scratch build a WWI aircraft, it would be the Fokker Eindecker - maybe then this wing set would be a part way to achieve that.