The kernels effect a lot of things like processing speeds, whether or not you can overclock you're processor, and even charging and battery voltage output. I am by no means an expert or programmer I have just messed around with kernels... Some of them greatly help battery life like KingXKernel Kingy fresh #4. Also no you do not need a custom ROM for a Kernel.
I would try Virtuous 3.01 (it just got released yesterday) with the custom kernel. It's been great for me. I had his 2.7 in for about a week and I did see a difference in battery life and it looks like 3.01 is at least the same. It's a sense rom and gives you the opportunity get rid of some bloat.Just rooted the wife's Dinc, what is the best rom to load for battery life?
Looking for something close to the stock 2.2 Just better battery performance.
I would try Virtuous 3.01 (it just got released yesterday) with the custom kernel. It's been great for me. I had his 2.7 in for about a week and I did see a difference in battery life and it looks like 3.01 is at least the same. It's a sense rom and gives you the opportunity get rid of some bloat.
Redemption and KK#5 is insane.Try that combo out.