Blade Help.

Depending on how you want to loop you may want a flexible blade.
But for precise blocking, you may want a stiff blade.
So there's some contradicting requirements here.

If you want to stay in the same speed range of W-6, try Nexy Lissom. It has a nice square handle, too (actually, more rectangular than squared).

If you want a crisper feel but still plenty of dwell time for loops, try a composite blade with hinoki outer plies, such as Nexy Arirang. If you want it crisper and faster, too, try Tibhar Inca or Bty Photino.
These Nexy and Tibhar blades have a ST handle with perfectly flat top and bottom surfaces, which helps a lot in getting a precise feeling of the blade angle.

See nexy.com for pictures or the review threads (accessible from the Nexy clan link in my signature).