Help with speed of advancement

[Arjos]

They are good, but far too costy at that stage...
Ashigaru replenish very fast, in campaign they are the best troops imo, you can sustain heavy casualties and be ready to fight again the very next turn with a decent general...
If you can manage to push towards Noto and capture it, that would be very good, just beware the religious unrest...
Once that's done go all out against the Hattori with your new armies, keep an eye on the Uesugi though...