I checked out that kernel. It isn't an sbc kernel.
The sbc kernels allow the battery to charge more fully if you leave the phone on and let it charge, like overnight, for instance. Like 10% more, I have read.
As has been mentioned, you don't have to use setcpu with cm7/tiamat. If you have that, and maybe with your kernel, as well, when you go into phone settings you see something called Cyan... Settings. Click on it and you will see "performance settings'. Click on that and you get a warning, just be careful. Right at the top of that list is stuff like max and min cpu freq settings and it allows you to choose your governor. In this case, Smartass is cool. It seems to act like a screen off profile in setcpu, built in.
another battery saving idea is JuiceDefender from the market. It turns your radios on and off intermittently, as well, so your phone is not constantly hunting for a signal in weak areas. it just pops it's head up and gets the info periodically. Set in balanced mode it 'balances' battery saving with you getting your emails in timely fashion.
some folk just completely turn their 3g off until they want it for something. i can't remember what that does to emails but texts and phone calls still get through.
Also, how much stuff do you have syncing, and how often? you can change how often in settings and that will help.
also, have you updated your prl and profile, in that order? that is supposed to help too.
Definitely know tiamat with sbc will add to your battery life.