I need some help to pass time on a friday afternoon at work

So I thought I'd discuss strategy - specifically opening strategy for a battle with fairly standard sa/ys army where I'm the agressor (and where I'm counting on winning).

I usually start with the units in the default positions and formations, the only change being putting the archers on loose formation.

I most often make two largely identical main groups composed of the following:

each gets one of the two frontline archers and at least one more. This is the frontline of the group. Behind these i place the infantry at regular intervals, ready to charge through the archers when needed.

Hatamoto, yc and ca are used primarily as pursuers (ca as skirms too naturally).

These groups are then advanced across the battlefield on the left and right side until the enemy presents itself, and then we stand off with one and attempt to flank with the other (and the loose units).

That's basically it - is there something basically wrong with this setup. I could sure use some inspiration.

I had a funny battle yesterday when a fundamental flaw appeared in this strategy. I was Takeda attacking the Oda province just west of Shinano. We had the same number of troops, but he had ya to my ys, so I wasn't worried. The province has two peaks on the attackers side of the map, so I sent one half of the army around each side. When my leftside army made it to the top of their hill it kinda bumped into the full Oda army.

The right side of my army was climbing a steep hill far away, so I had actually isolated myself. Well I still hade the height advantage so after some archer fire I charged my 4 ys against his 7-8 ya and 2 ys. All my units wavered, and I charged the 2 sa aswell, finally breaking the ashies. It was kinda close for a while though.

Naturally this tactics often results in one group taking the brunt of the initial fighting, but I often find, that the other group kan rout the enemy when they arrive.

Any comments (plz)?