Its a shame SST never got to "evolve" (and I don't mean the crappy Battlefield Evolution proposed re-vamp either) - but certain ideas that never made it into the Game as a whole.
The experimental Sniper Rules from Signs and Portents were quicte excellent, and surpisingly balanced for a first Draft.
The Forth would have been a fantastic and unique Army, and though Mecha inspired totally unlike any other Force on the market currently (no, NOT even the bloody Tau).
The Coven were a B-Movie inspired evil babes Army - with imasculated male slave troops - a superb idea!
I had even started working and play-testing my own rules for Hybrid Platoons - so you could "mix and match" your troops more easily, putting them in a more competitive position play-wise with other Sci Fi Wargames.
All the wonderful potential for the game got "canned" when Mongoose Dropped SST like a hot coal (and yes I am bloody bitter about it) with no real satisfying reason why (more than one was offered up, not seemed particularly believable or logical).
So, for those who don't have access to the aforementioned rules and ideas - I've uploaded them and they are provided here for completeness - and are not intended as an infringement on anyone's copy-right.
The Forth and the Coven Rules are provided in their original raw format. The Veteran Squad Rules, The Sniper Rules, and my Rules/Ideas for Hybrid Platoons/Forces are formatted to look like the Core Rulebooks.
C'mon you Apes - D'you wanna Live Forever!