I don't know much about how video games work, I can spot something that is broken, but as for the fix I wouldn't have the first idea, so i'll leave that for Konami to deal with, but they MUST fix the shooting, penalty's and the d-pad dribbling - there's an analogue stick, use it. Oh and of course, more licences and likenesses are required.
I do however know a bit about football, so i'd like to see a few of the following ideas implemented:
1. More real stadiums, expand the stadium editor, improve fan chants and improve the graphics for the fans.
2. Improve the commentary! It's been the worst part of the game since ISS Pro and is an integral part of the match experience.
3. Improve the goalkeepers, make them superhuman, cheat with the AI if need be, just don't make them so damn rubbish.
4. Weather has to be improved. F1 2010 has a brilliant dynamic weather system, why can't PES? If it rains, the ball should skid, if it rains too much the pitch should become boggy, players should tire more quickly, the match should even get abandoned half way through. English players stamina should reduce if you're playing in 50 degree heat etc. Don't just have weather effects, make them actually impact on the gameplay.
5. Different pitches should have different sizes, different lengths of grass etc. In Master League you should be able to set the parameters for these stats to suit your team. E.G. Barcelona have a huge pitch with short grass. The pitch should suffer realistic wear and tear during the season.
6. Edit mode should be a lot more detailed and easier to use. Allow us to save as many emblems etc as we can fit on our hard drive, don't limit us to 46 or whatever it is at the moment. Don't persist with the Vision Camera, allow us to save pictures on the hard drive and import them into the game. More boots, more hair, more faces... Make it huge.