You mentioned historicals.
THW, the same folks that make ATZ have NUTS!, a WW2 game using the same mechanisms and have added a weird WW2 supplement as well.
http://www.twohourwargames.com/ww2.html
A system I playtested and have written stuff for is Ambush Alley Game's (AAG) "Force on Force". It covers moderns, and there are multiple supplements either out or on the way which cover several time periods and theaters, from Vietnam, Africa, Cold War gone hot... Their SciFi version, Tomorrow's War comes out later this month. AAG uses a reaction mechanims different from THW, but is still very interactive. Games are typically platoon plus - company minus on each side.
http://ambushalleygames.com/products/store
I recently got the new game, Saga by Gripping Beast which covers dark ages warbands. It looks like a lot of fun. Each player controls a warlord and a few units of 4-12 figures of Vikings, Saxons, Normans... Warbands will be from 25-73 figures depending on the troop qualities you buy with your points.
Everything mentioned above allows the use of figures from any company you want to buy them from.
Jake