Rampage was their first new architecture since Voodoo1. I recall reading that the project was a mess of feature creep and was originally planned to be released much sooner (without D3D 8 features). VSA-100 was a stop gap to have something new-ish to sell in the meantime, another extension of the Voodoo architecture.
Yeah, Banshee/Voodoo3 were their attempt to get OEM sales and it worked pretty well. Voodoo Rush was basically their first attempt at that but Rush was awful. I think Voodoo3/Banshee were as good or better an option as i740/Riva 128/TNT/G200/G400/Rage 128/Savage in most cases. Glide support was very useful at the time, and in general you knew the games were tested with Voodoo cards. 32-bit color was almost useless with those other cards (even GeForce 256 was iffy IMO), and the Voodoo 256x256 texture size limit wasn't a huge issue yet.