single based, (really) fast play ruleset ?

[vodkafan]

Panzerfauste.
It's a fantasy set, but the first edition version worked well for historical skirmishes if you ignored the fantasy bits.
Haven't actually checked the new version to see if it is fundamentally different, but played a demo version at a show and it felt the same.

Our group has also used Panzerfauste for historical skirmish, it has nice mechanics. We  played multi-player with a section (squad) each the time I played it. I guess one player could handle a whole platoon easily enough though.

[SteveBurt]

Rapid Fire fits the bill, although it's not my favourite set because of the bizarre mixing of scales. 1:15 scale for figures, so you have multiple battalions on the table, yet there are rules for grenades!

[sundayhero]

New version of the rules "Groupe Franc" (scale is similar to chain of command), with small details corrected/added :

http://reglesvv.monsite-orange.fr/file/27f178b1a8027cf1c7980d95e408f01e.pdf

and the french forum to speak about the rules/ask questions :

http://thebrushbrothers.forumactif.fr/f64-groupe-franc-combats-d-infanterie-au-1-1