I smash 600 of 20 overs and then have to chase it down myself because the AI can't get even to 150.
Hmmm, I find that a bit hard to believe... but devils advocate, I found a way around the AI issue by simply lowering all the stats of my "bowlers" via player editor, then if I want to "chase" a challenging score - the AI batting is much more aggressive; AI will routinely get 190+ which on "HARD" I always find reasonably challenging.
...But then, I'm not a huge gamer... There's also few patches out there to up the difficulty level, but I digress.
I think it's more an issue of making the game evolutionary, so Hard really does mean HARD. Everyone is going to eventually find ways to beat the game (that's a part of gaming) but certainly the way AI reacts to big scores, chasing runs and field sets can be massively improved upon in any new generation of cricket gaming. You also gotta remember when C09 was release (and even C10) T20 Cricket was still evolving, certainly in regards to batting. Nobody could've predicted how Slower and Spin bowlers have become vastly more important in T20 and how quickly teams (and players) have been able to find ways to score big, and quickly.
There's a wonderful quote out there by one of the inventors of T20 Cricket saying he wouldn't see anyone score a T20 "Hundred" in his lifetime. Which is ridiculous when you think about it, but now 150 is on the cards. Game developers can't predict these evolutionary changes of the game, unfortunately. Even Test Cricket has come a long way in three years, it's a much more aggressive format and that's partly due to the influence of T20 Cricket (some will say it's to the detriment of test cricket) but teams are amassing runs, scores and getting more results more quickly.
All things, three years ago, you wouldn't have been able to predict.
Having a more dynamic difficulty setting (and evolutionary AI that almost can predict the way you play) would go a long way in improving all this.
Another improvement might be moving back towards the concept of
Batting Classes where you have a Definsive, Moderate and Aggressive batting style in each team (like in EA07) so certainly players are constrained to bat in a particular style. They have weaknesses and strengths built into the AI. Those differences get more/less aggressive depending on the difficulty setting.