Ideally, if processing power wasn't an issue we'd have Britain using battallions, and pretty everyone else using regiments or battallions too-but the brigade system has merit. If anything the brigade system ought to be accepted more fully, rather than having two regiments of infantry we'd actually have two brigades-although that's more of a cosmetic measure, partially because the OOB at regimental level is a mess-despite everything from division upwards being meticulously accurate (so far as i can tell).
Its a good point about the triangulation of units, it would be one hell of an event-as you'd either get every Brigade/Regiment losing some power in return for a whole load of replacements (and have to build the new units), or a coding that would somewhat accurately create the new divisions in relation to the existing divisions. With Mortars and Engineers we could just see units representing them, while Stormtrooper seems fitting to an upgrade or generals with the training officer skill. Machinegun units have been long discussed on the RuS forums, and both sets of arguments hold their own rather well, yet if, unlike RuS we are talking at Brigade level MG units fall into the same category as Battallions-interesting addition, but too in-depth for this kind of scope
I guess what I'm saying is, the current system has merit