A few days ago I just won my first campaign (long H/H) with the Chosokabe. The endgame was pretty easy, although the beginning and just after the divide were a bit tough.

I managed to keep the Date as my ally for the whole game, which helped a lot since I could trade with them.
I am not sure if I can get the statistics back from the game, but I remember my total earned koku was about 3 million, of which over 2.5M went to unit upkeep :)

My final tax collection was around 27000 koku per turn, trade was something like 8k if I remember it right. I played the "surplus" tactic on economy, and my food surplus was 39 at game end.

Next I am going to play as the Shimazu and see if I can play without using too many archers. My "house rule" will be that I don't use samurai/monk archers at all, but lets see if that works out.