I hate to ask BUT!!!!

[BUSGO]

For a mixture of highway riding and city commuting, the Metzeler M3 OR Z6 tyres are outstanding for grip and life. The M1s are a bit softer though.

I don't know what you don't like about the BTs but the new BT015s on the K8 are brilliant.
I have been using the Metzeller M3s for about a year and swore by them but I find the new BT015 is better.

Considering some of the stuff that used to pass for tyres in years gone by, just about any new compound tyre will be pretty good but consider that the tyre profiles made by Bridgestone especially for the Hayabusa have a profile designed to give better grip and stability through high speed corners, not necessarily tight twisties.