I didn't have any issues with sleep/wake on current kernel and build (there is pm.sleep_mode=1 in my startup.txt but it's probably irrelevant). Camera can take stills but not video - known bug.
If you follow
this tutorial you should be able to build your own system image with minimum effort. However there are few things to note:
1. You need to use Ubuntu 10.04. It won't work on older version and there are additional steps in Ubuntu 11.10 (not covered by this tutorial).
2. First build takes absurdly long time. It was something like 10 hours on my Linux VM. May be faster on quad-core native Linux machine but still it will be hours.
3. Using OpenJDK may not work! It's better to use latest sun-java6-jdk.
4. In step "Build Dependencies" you need to do everything as described with two exceptions.
a) signed-dream_devphone_userdebug-ota-14721.zip is no longer available on HTC Developer Center - google it.
b) HW3D driver is outdated. Google hw3d-20111216.zip.
5. Last thing to do before build is add booksphone.apk manually because it's missing from the latest gapps package. Google it and place under vendor/xdandroid/msm/proprietary.