MP is predictable? Most nations are not one trick ponies, and especially the ones that are (say EA Abysia as an extreme example) need to diversify eventually (and rather sooner than later) to have a chance against a good opponent who reaches a counter to your one trick.
They are predictable strategically. Like, if there is Nifelheim on the map, you can bet your arm and leg a "challenging" player will have a E9Nx pretender and will spam niefel giants like there is no tomorrow. The burritos guarantee jaguar warrior spam and fire bless, etc. Access to magic and items is also all but predefined by nation's mages and by pretender (who is originally all but predefined by nation's most cost-effective unit). Sure, they eventually diversify... to summon tarts, wish for chayots and forge the same 2-3 combinations of items. Yawn.
By summoning mages and troops with your pretender for example, before tarts too since next to no nations can actually reach Tarts (+GoH/Chalice) natively anyway.
Curiously, half the threads on patches/balance/requests on Shrapnel boards sum up to "bawww, do something so that people would occasionally field something other than tarts by the lategame". So far, nothing worked, even the ridiculous "shattered mind" (retrofitted specifically to nerf tarts) only meant you need 25% more backup tarts.
Sure, on tactical level, you can be dramatically surprised by anyone, anytime, but strategically you always know how every "good player" is planning to develop, because any other way for a given nation would be suboptimal. And when a game's main selling point (for me anyway) is having 2000 units, 800 spells and 600 artifacts, I'll take a dumb AI throwing everything and the kitchen sink at me over a smart AI spamming the 10 most cost-effective thingies ad nauseum, any time of the day. In my own little gaming world there is only enough space for one minmaxer
And since it is absolutely unavoidable that 99.9% of the game's content is doomed to be suboptimal and cost-ineffective, I want
someone to employ that content when I don't.