iscorefilm, I have to ask, which VSL strings libraries do you have? If your signature is current, and all you have are SE related libraries, you are not getting anything close to the full picture of all the articulations that are part of the full DVD libraries.
I also started with the SE libraries, and they are very good. But, for maximum realism, there is no substitute for the full DVD string libraries. The dynamics patches are of importance, and the additional bowing techniques round out the primary articulations in the SE libraries.
In terms of my own RL experience, of the various marketplace offerings I am familiar with, in terms of solo double-bass, only the full DVD VSL solo double-bass library begins to approach what I am actually able to do with a bass bow (side note: natural harmonics are of great importance in the solo bass literature, and VSL, unlike others, includes them). VI Pro 2 helps as well, as one can begin to program more variations for any given bowstroke, much as a real player will do.