Honestly, I don't think anyone knows what to expect from the patch when it comes to gameplay changes. If those are the primary reasons you don't want to play the game, I suspect you will not be satisfied, even if you wait for the title update. I'm willing to bet the scouting/staff stuff will not changed until FIFA12 (probably in a different form than 10). It seems the career mode fixes will be focused on things like player growth or other apparent bugs (cup scheduling?
).
As far as CPU aggression & 1v1 play, while it's possible the FIFA team may tweak it to your liking with the patch, it's also quite possible you will continue to be dissatisfied. I haven't played much offline yet since I've been playing clubs, but I haven't seen anything in my time to make me think the CPU is any more aggressive in 11 than they were in 10. I know they seem to be harder to break down due to better positioning/marking -- could be part of the issue with 1v1? -- but I had to alter team tactics to enjoy playing the CPU in FIFA10 and thus far in 11, haven't felt the need to do so. Perhaps you should consider exploring this option if reduced defensive pressure would change your overall opinion of the gameplay.
Or just cut your losses and trade it in. You're not the first and won't be the last that buys the new iteration of game they enjoyed the year before and decides it's not for them.