I hired a Tracer in Spain so I know what you mean, good bike but not a Fazer. 1st impressions of the Versys are excellent. Bearing in mind I am still breaking it in and have only 300 kilometers on it and I am not supposed to exceed 4k revs, the low down pull is as good or better then the Fazer. The clutch is almost silly it is so light. It does make slipping the clutch more difficult but the low end power is so good that I just don't think that will ever be a problem.
Lights are crap, with only a single H7 bulb for low beam and another one for high. Having had twin HIDs on the Fazer for the last few years, there is no way I could go back so LED bulbs are on order and if they aren't good enough, I will go the whole HID projector route.
The throttle is not quite smooth in the transition from fully closed, but the Fazer was exceptionally good in that area. It is not bad, but until ECU remaps come onto the market, I think I am going to have to live with it. The suspension is in a different league, but then it bloody well should be since I am comparing a brand new long travel setup with a twelve year bike (even if it did have an R6 shock).
The best description of the difference I could come up with for my car driving wife was that it is like going from a 12 year old sports saloon to a new Range Rover.