Batteries (not the power kind...)
I'm supposed to be putting together an outline for the Compendium, which should include rules not in Core, Highguard, or the Companion... I think the battery rules are in Elements? They should be tied to crew size and I think I can be a little creative... once I find the rules.
Unrelated to Highguard, but not the Compendium: Will also try and pick some useful bits out of Mercenary... and see if I can sneak in a Snapshot rule while I'm at it.
(Yes, Matt, I'll be working on it... soon as we get our one remaining cat back from the vet... after that bill, I'd better write a couple of books this year...)