Adjusted Timeframes
Minidrives were expensive additions to any mech. Ves could foresee many scenarios where a miniaturized warp drive could make the Firestarter Project a lot more useful, but the rationale wasn't as strong as with the C-Man Project.
The C-Man Project's case was stronger because Vincent wanted to turn it into a pure melee mech. This meant that it could not function at its full potential if it wasn't at point-blank range with its targets.
This imposed a heavy limitation on its use and made it all the more important for the proposed expert brawler mech to be good at moving around.
The need for rapid traversal was much less for ranged mechs. As long as the ranges weren't extreme, it was perfectly viable for ranged mechs of many different varieties to inflict effective damage against distant targets.
However, that did not mean that it was useless to equip the Firestarter Project with a combat drive.