I'm quite partial to the Richard Borg games BattleCry, Memoir 44 and Command & Colours. They are ideal for 2 players and our club has actually bought the first 2 and keep them in the gaming cupboard. If you turn up without anything planned you can usually find someone to have one if these games against.
On Boargamegeek in the Battle Cry Page there is a variant set of rules for the game called Advanced Battle Cry Deluxe Edition (find them under Files). These really improve the game and make it more "ACW like". So much so that we play these rules on the tabletop with 20mm plastic figures.
You could use the Kallistra Hexon System but these are quite expensive to make up a board for BC. So I purchased a 4 inch plastic hex template designed for quilt making from http://www.roybland.cjb.net/. With a bit of practice I found the best way to draw the grid is not to fully trace around the template but only to draw the straight sides and then only about 3/4 of their length. This hides any errors as you get near the sides when the grid can start to drift but also looks very good on the tabletop. I then purchased some Kallistra singles and hills to place on top of my drawn grid.
A new group has now opened called Hex/Grid Yahoo Group which is for like minded people to discuss these hex games, convert current rules systems etc. There are a number of hex tabletop rules available free from The Antwerp Fusiliers.