On the other hand, the vast majority of actually Travelling classes (Classes that do travelling as opposed to sitting on their postiers at a University, etc.) have Armor Proficiency (Vacc Suit) as a first level, here is your list of feats for taking this class, freebie feat. Further approximately 25-30% (I may be a little off here I didn't feel like doing prob numbers, it is a close guesstimate) of homeworlds also include the feat Armor Proficiency (Vacc Suit) so in all honesty, there aren't all that many typical Player characters that won't have the feat.
I still like the fact that Armor Proficiency (Battledress) is required to get Weapon Proficiency (High Energy Weapons). As only the PGMP-13 and FGMP-14 actually require Battledress and Battledress is TLD but the PGMP-12 is TLC. So an average stellar army, that is TLC, can't use the stated squad support weapon. (Oh and 76 Gunmen ignored this requiremnet rather nicely.)