The Alexander the great scenario contains a lot of slic. Therefore if you like to make such a scenario you need a lot of time. There is a WW2 scenario by Activion. Peter Triggs resliced the defence of France part some weeks ago.
Here in the Apolyton Database you can find two accient scenarios by Nick Spencer, AKA Hannibal Ad Portas. The first one deals with Dacia, the one deals with Carthage and their 2nd Punic War with Rome, regarded by most as Hannibals War. This is also a non slic scenario.
I found another one on my hard drive called Dawn of a new Millenium some slic but in an beta stage. Unfortunatly I have no idea who is the author. Another one is Mars 2020 by Immortal Wombat. It deals with the colonisation of Mars unfortunatly in beta stage, too. But you should give it a trial. BTW how far are you with it Ben? You can find it here:
http://members.aol.com/wvrs4/ctp2/ctp2dl/marsreadme.htm
Another one by Immortal Wombat is the One City Challenge scenario you can find it here:
http://members.aol.com/wvrs4/ctp2/ctp2dl/occreadme.htm
I found a under water scenario unfortunatly only in German and it looks that it is an alpha version.
There was another ancient scenario but I forgot its name.
And there is another one, made by Tobias Teetz. It deals with the Seven-Years' War, it doesn't contain any slic either and the translation from German into English is not complete, but I think it is not necassary. At least it has an English readme and you need Apolyton Pack installed!!
You can find this scenario here:
http://home.t-online.de/home/dteetz/
The direct links are:
http://home.t-online.de/home/dteetz/FG_SPIEL.zip for the game files and
http://home.t-online.de/home/dteetz/FG_TEXT_SOUND.zip for the sound files.
-Martin