This content is for an older version of Synfire. The current version is more streamlined and advanced, but most of the functionality shown here still exist.
Learn how to extract the sound names and banks off a loaded VST/AudioUnits plug-in. As many synths support this, it will save you a lot of work when you need a device description. Since most samplers (sample libraries) do NOT offer this support, the video also shows how to deal with those.
The pitch range of a sound can be scanned automatically. In any case, you need to check if the playing range of a sound matches its physical limits and whether the Typical Pitch actually is the true "sweet spot" of that sound. A bass is not worth anything if it plays at high pitches.