eh, like I said in another thread/post, I think its best if you start out building them one at a time, and then later-on, when you have enough man-power, influence, and resources, you can "mass produce" units, so when building one Imperial Lancer, you can slide the cost to build actually 10 units at one time.
we ARE looking at the possibility to field 200-500 individual men/beasts on a battlefield at one time, right? At least?
Also, you can group 10 or so units as one formation, to give them all the same orders, and be represented by one portrait on the short-hand "regiment selector" ... although initially you have the option to build one man at a time, when you only have a few people and a few resources at your desposal.
I think keeping the transition from one man units, to make a total team of maybe 5-20 guys, into 10 man units, to make a total ARMY of 200-300 guys, into a relatively smooth process, is key. Therefore, I think making a customizable slider, from one - 10 men to be built at a time, as well as some sort of regrouping function after losses from battle, would be a good thing.
Edit: one of my main turn-off of Heroes of Might and Magic was having 200+ guys being represented by one person ... that whole system as a 4x game seems pure bollox to me anyways. Lesse, im gonna place 2BILLION cannons on ONE TILE. yea .... that makes sense ...
