Captain Daisy, with Monty Mole or Hammer Bro (depending on the situation) and Dry Bones in the wings, and Boo on defense.
My secondary team is Captain Yoshi, with Hammers and Birdo in the wings, with Toad in the back.
Daisy's team is a but trickier to use, but it can be even trickier to stop. It's scoring relies heavily on trick plays.
Yoshi's team is a more conventional scoring team, it can put up a tough offense, and an equally tough defense.
I think you have one Birdo too many. And you don't have one single competent passer in the bunch. A strong defense should be able to eat you up. If you like her shooting, maybe get a Hammer Brother to keep the shooting but gain some passing skill.
Dry Bones isn't too bad on defense, but his passing leaves alot to be desired, and it can help to have a great passer on defense to get the ball out of your half and to hook up the wings with some one-timers.
Get someone who can pass, or good defenses will intercept, slide tackle, and generally pick your offense apart.