Personally, I love tactical games, but hate the "artificiality" of scenarios (e.g., on the last turn you launch a do or die attack, because losses don't matter). I've always felt that it should damn well be possible to have a game that properly spans the gap between strategy and tactics. Especially in the ancient era, this is what war ultimately tended to boil down to - all the fancy maneuvers in the world are worthless if they can not be translated into battlefield success (as Darius found out).
Obviously, there is no need for a game to combine tactical and strategic aspects to be good, but IMO any game set in the pre-1820s era cries out for such an aspect since essentially, strategy and tactics blended together, and the monarchs and princes who ruled the nations were very often the same who fought on the fields of battle.
In Imperium you don't play Consul and Centurion at the same time, you always play Consul (or Consuls) no matter where you are - in the forum, on the strategical map, or on the battlefield. At least if I do the job right.
The problem, of course, is that there is always a risk of creating two mediocre games, rather than one good one. Who knows, that may be how people will view Imperium - though I certainly hope not.
Another problem with strat/tact mix is that you really need a good AI in both parts, or you'll have the entire game being broken. In particular, the tactical AI
must be able to challenge the player properly - and that is extremely hard for a computer. This either demands extreme ressources (like for Shogun:TW - and even here the AI is not really all that good) or you have to make the tactical game simple/abstract (like in Conquest of the New World - which has one of the best tactical sub-games I've played; extremely simply, yet also very fun, IMO).
The latter approach is the one taken in Imperium. The balance is, of course, that simplifying it too much can make battles uninteresting. So this is a difficult balancing act.
Actually, I though Napoleon 1813 (which I bought second-hand) was a brilliant game. Or rather - a brilliant concept. Where the whole thing fell to pieces was with a ridiculously inept AI (I recall one game where I marched right on Berlin and ended the war in 6 weeks or so), a bad interface, and a hopeless tactical game (units moved around more or less at random - sometimes they didn't move at all, combat results were inexplicable - even with the manual, and oh - did I mention a truly lousy AI?). But so much potential.

Anyway, to get back to Imperium. Where I want you, in Imperium, is to try and immerse you into the thoughts and mindset (or at least what I believe to be the thoughts and mindsets) of a Roman Consul, Carthaginian Patrician, or Hellenistic King. In other words, when you declare war in the game, you do so for much the same reasons as they would have done. When you sue for peace, you do so because you know not to do so would be ruinous (unless you're Roman, in which case you stiffen your upper lip and mutter something about the Phyrros and Claudius). Essentially, I'd like to give the kind of people who roleplay and write long AARs in EU the chance to roleplay and enjoy a strategic game in Ancient Rome,
without constantly having to rein themselves in from perfectly sensible (in a gaming sense), but utterly unhistoric behavior.