Can't you use the zombies and skeletons as skeletons for
KoW/
WHFB, and the 1/72 historicals for historical games...?
I have no idea how many historical mass battle rule sets there are. I've recently found out what kind of rabbit-hole it is, just looking for company+ level WWII rules. Some well-recieved ancients/medieval rules have been pointed at and linked to in the 6mm topic further down the board - Hail Caesar, Sword and Spear, In Death Ground, Impetus, DBA and DBM - but I've no doubt that's only scratching the surface of what might scratch your particular itch. I can tell you that all of those mentioned are element/unit based games like
KoW, but with more command mechanics and differing levels of complexity; while the games War & Conquest and Clash of Empires are more Warhammer-like. (Taking their cues from the
OOP Warhammer Ancient Battles) Good enough list to start with and google?
For Napoleonics I'd be even less help. The local club used Black Powder for an ACW Gettysburg game, and seemed to like it well enough, with a few movement houserules. (I liked it myself, though the movement rates seem designed for the humongous tables played on by Rick Preistly and the Perrys
et al.) There are a number of Napoleonic supplements for the game, but I'd hazard Napoleonic rulesets are like beetle species: outnumbering almost everything else by a fair margin. The local club were dead-set on switching to the latest edition of Napoleon's Battles, at least, but it seemed a bit charty for my tastes.