A few tricks Ive learned:
-When setting up, tuck your chin to your chest....that will put you on your traps higher.
-There is a point where you are setting up, where your setup looks AWESOME, then you comletely flatten out (probably addressed by someone else on the forum already), but, as you said...working your feet back will help. try turning your heels in towards the bench with toes pointed out. That will help 1)keep your feet flat, as you said you compete IPF rules and 2) move them back further to stay tighter (learned this from Niko Huslander and he KNOWS HIS STUFF, watch him on youtube lol)
-If you want to strengthen your lats, I would do more rowing with a barbell or dumbell than and sort of pulldown.....I always feel you can gain more strength for pressing power that way.
-pull the bar our to the bottom of you lats....when you think about how you do a pushup, you utilize ALL of your lats, not just part of them, so being the bar out until it is completely on your lats....if your setup is correct, the weight wont even feel like it is there! if you do this, you wil also have some elbow tuck, meaning, push your elbows to your feet, DO NOT COMPLETELY TUCK, as it will kill you on the bottom, especially during speed work.
I hope this helps, let me know if you need any clarification or have any questions!