I developed a new strategy but haven't exactly tested it yet
H= Hastati or Average quality infantry
P = Principes or better infantry of your army
C = Calvary
T = Triarii or equivalent
_____________H_________
___________H___H_______
_________H_______H
_______C___________C
___p___________________ P
_____P________P______P
_________T___T___T____
The formation is another combination/Variation of my two favorite formations from the Sengoku Period: The Crane's WIng and the Arrow Formations. the Front is obviously an arrowhead while the back looks like an open Crane's Wing Formation. the back should be spread out wider than the arrow head. the ideal use of this formation is for use against line formations or wide spread ones, probably works well with the Crane's Wing part hidden in a forest. The concept here is that the arrow head charges forward into the enemy center, hoping to get their wings to flank/envelope the arrowhead, making them concentrated in the center. then one of two things can happen: 1 the arrowhead then retreats with the calvary fending off any enemy calvary that come too close. the arrowhead then retreats behind the crane's wing which envelopes the enemy (this one works well with an ambush). 2 The crane's wing then advances to envelope the enemy surrounding the arrowhead while the arrowhead backs out far enough to prevent bieng enveloped.
Not tested yet but if anyone else tries it, please tell me the results