Are you still using default line sliders, team tactics and player stats? Because those need to be changed if you're looking to up CPU attack.
1. Sliders: I switched to regularcat's line sliders, they push the CPU up and help create real midfield battles. Line Height up (mine is 75) and Line Length down (mine is 5). Also, the higher the marking slider, the more aggressive the CPU plays.
2. Teams: Edit team tactics and raise defense pressure, the CPU will hound you further up the pitch. Raise defense aggression as well if you like the CPU to push/tackle like crazy, I personally don't like it but it creates more fouls. Raise teams' buildup speed. Change teams' default formations and assign attacking formations. Change players' instructions to join the attack. There are also team trait codes that can be assigned to boost team attack, as well as a handful of other team tactic codes that can help (raising long passing and lowering short passing for example).
3. Players: I raised all players' long shot and shot power ratings to 79-99. This creates hundreds more players with the distance shooting specialty, so you will see more CPU shots and less stupid CPU passing in front of goal. If you play career, you can adjust youth player generated values to match these db changes (I believe, but you're the expert there). Also, assign players high attack work rates and low defense work rates.
It honestly comes down to this: we can wish it was better, or we can change the way we approach the game and make the necessary slider and db edits.
EDIT: It occurred to me that locating the d-pad assignment codes, and setting CPU to high attack, would boost the CPU attack substantially. When I use the d-pad to push my players up, it doubles the number of my players in the CPU box, and it pushes my defenders way up to join the attack. This may well be the best way to boost CPU attack positioning and mentality. I'm going to take a look and see if I can spot where those d-pad assignment values might be located, hopefully it's something that can be edited.