A 210mm would likely have less of a flat section than any longer gyuto. Nature of the beast kind of thing. Less length to have the flat section.
You might consider a funayuki shaped gyuto. They tend to have long, flat sections that are ideal for push cutting.http://www.chefknivestogo.com/kohhstfugy24.html
There is also the kiritsuke shaped gyuto's.....now they're all out flat profile:http://www.chefknivestogo.com/kohhstki24.html
However, do keep in mind that these are very flat and many people report difficulties using them.
The Masamoto KS gyuto do also share that flat profile and KS shape has been copied many times.
As for the handle being small....not really heard that very much of the Kono's and I don't think they're on the small side for wa handles.