I would love to replace my XRR with something better, if and when something better came along. KTM is 'better' probably, but not $10,000 better.
Correct me please, but isn't the WR250R based off an FZ-1 motor, or R1, or something? If that's the case Suzuki could easily make one based on the Hayabusa, and Kawasaki off the ZX-14. That would put it at 350cc, which isn't far off from 400. I wonder how well the DRZ sold, meaning did Suzuki make it's money off the design?
The bike the OP, and a lot of us, is wanting may very well be in the works. Honda, Kawasaki, and Yamaha recently came out with a new version of the 250. Maybe they are counting numbers to see if a 450 is worthwhile?