British Grenadier for "mainstream" actions, Sharp Practice 2 for skirmish games. Having been wargaming the AWI since the Airfix sets came out in the 1970s, I've tried most of the rulesets that have been published in the intervening 40+ years and these two tick all the boxes for me.
I'm currently building a Sharp Practice force for SP2 based around the 71st Foot in the South, where they created a perfect combined arms force by forming a 50-strong light dragoon detachment.