Need 41-2-3 advice

[Striker122]

as the description says im playing a 4-1-2-3 formation or if you like its a 4-3-3 formation with a DM (like what chelsea play in game) its fairly defensive ever corner i have 3 at the back when attacking (considering changing it to 2 and just have the other lurking on the edge of the box) and i only leave 1 up top when im defending, the tactic has worked fine in most games i have used it i was averging 2 a game in one of my saves (which i played for around 8 seasons) although every game i played i was in the lower leagues, the highest i went was as plymouth argyle in the championship in which first season i got them to 4th and lost in the final of the play offs, although the next few seasons i ended up finishing mid table.

basicly i made a man city game ( yea i know money grabbing), i made this save for 2 reasons 1 i hadnt played a prem game in FM10 and 2 i wanted to try my tactic in the prem as it worked in the lower league it should work in the prem right ? i still wasnt conceeding many but i wasnt scoring much either
heres how my team is set up (in terms of roles )

GK
FULL BACK CB CB FULL BACK
ANCHOR MAN
BOX TO BOX BOX TO BOX
INSIDE FORWARD INSIDE FORWARD
POACHER
i had the players that in any normal team you would prob win the prem by 20 points.

i was just wondering would my tactic work better if i changed one of the box to box players to advanced play maker to aim to get assists, and possibly even change the poacher to a target man. thanks for any help/advice i get and sorry if the way i laid out my post is abit confusing