zero trail hubs are excellent, they improve the handling and are much stronger obviously. They will make the steering feel more direct.
The 7.5 deg yokes are worth trying for sure, it MAY be a bit too much though, I prefer 5 deg, but that's just my choice. The more castor added the more power on steering you will get, but will loose some steering coming out of the corners.
I couldn't believe the difference when I put an extra 5 deg castor on
