100+ turns wow, you're taking your time. I was done on turn 100 sharp, which is still pretty slow...
I didn't capture the Mouri daughters that early either. Still, it's a good idea to go west first, then east for Uesugi and Takeda. Takeda cavalry units can be tough, but there's various ways to deal with them. Personally, I have two general strategies for any battle. One is a team based of assasinations: 3 ninjas (with assasinate)+Yamamoto (Whirlwind) or 2 ninjas, the musketeer girl and Yamamoto, plus a tank, plus Aburako (the monk that has the restore action points ability). The other one involves Uesugi Kenshin (- 1 action point all) and Uruza with "precise shot" abil - also -1 AP all. The cavalry units rarely have more than 3 AP.
Also, unless you really want to unlock the Takeda commander character, don't bother defending their "rush attacks" when all generals attack in one turn.
If by Little Princess you mean Miki, then I don't know what triggers it. Ultimately, it's not all that important, since you can keep playing after, albeit losing a certain character. Just make sure you get her her lemons, and go look for her if she goes missing.
Also, don't bother much with trying to unlock stuff in True Route, since Kill the Monkey route will give you lots more leeway for that - there's no Demon Army.