There seem to be roughly three axes on which the strategic game is played: exo strength, enemy strength, and enemy army strength. Maybe time is worth a half an axis. These rough division are affected as follows:
Exo strength: based solely on gear and epic missions. It's really hard to not make your exos stronger, but it's also really hard to really push their strength upward too. It's an almost automatic slow ascent.
Enemy strength: Nothing you can really do about this one, it just goes up over time. Factories will decrease the levels of 7 of the 40-some bots by 1.
Army strength: Defined as how much and how strong of stuff you have to fight once the timer runs out, it's decreased by lion's dens, assassinations, and increases over time.
Time: Affected solely by command centers. Rushing the endgame means less manufacturing, means less time for them to build up a crazy army relative to your own.
The conclusions I draw from these observations are:
-Gear doesn't matter that much. As it becomes rapidly obsolete, if you fail to acquire some gear in a mission (dude dies, run out of hacker points, whatever) all it sets you back is some power until you find better gear than that. It's a pain for a few days, not for the rest of the game. That means the gear missions aren't that attractive if you think you're already good enough.
-Gear is everything. Factories weaken a fraction of the enemies a small amount. Gear makes your guys better against every enemy. If you have trouble fighting the enemies, and you cannot further optimize tactics (which, while difficult, is at least with respect to game resources, free), the best(/only) answer you have is gear(/epic exos).
-Factories are good for softening up Lion's Dens. They weaken everything in them. Also good for the final fight.
-The command centers are vital. Both for endgame loot (taking them early is likely a waste) and in order to prevent the army from getting too huge.
-Bahamuts are cool too.
- All the other missions. They...are. They are.
So what does this tell me about strategy? I don't really know. It tells me what I do outside of gear doesn't really matter until the endgame. It tells me there's nothing I can do about manufacturing besides rush the clock. In fact, I could probably spend the entire game without hitting a single factory, den, or assassination, and still be able to pull off the win. It'd just be annoyingly longer. But given the choice, I'd hit factories where possible.
I have a question or two. How do exos scale against bots? Bots have a nice predictable (extremely nasty) power curve. I know that exo parts scale on some arbitrary bounded range. 25%-100% AOE range per part, for instance. At what point is my exo strength the strongest compared to the bot strength? Given that manufacturing and levels both increase, maybe the game slowly slips away from me (or quickly slips away from me) until I win. But maybe as long as my gear keeps scaling, I hold my ground? I don't know.
It seems some amount of the difficulty comes not from the tactics, or the combination of supporting bot types, or carelessness, but from inevitably there'll be some bot who gets leveled way past the daily curve (since it seems random who gets leveled) and if the base bot is at all nasty then you wind up with a slew of accidental minibosses during the mission and not nearly enough turns or ammo to kill them all.