It's really hard to get good kernel suggestions as each kernel will work differently on different phones. My only advice is to download a bunch and try and see which one works best on YOUR phone from the best in terms of battery/stability/speed.
I can agree with this. I've done some testing using Powertutor and BatteryDog to get some facts behind my assumptions, and man can I tell you that there is no solid answer. Depending on what version of what rom I'm running, different kernal's really have affected my phone differently. With Miui 12.3 Slayer LFY was kickass. But UD 2.4 sucked with the same kernal. And now Miui 12.11 is horrible with the same kernal. I'm talking up to 8-10 hours difference, with similar usage. UD 2.5 and P3droid's low voltage kernal actually seem to mesh really well on my phone. But Sapphire was pretty bad with P3droid's kernals on my phone so..... I dunno man. It's weird because I've seen post after post of people reporting the exact opposite of what I've experienced, as well as people posting confirmation that they've gotten the same mileage as me.
Best I can say is test them all! They're all written by extremely intelligent and capable people, just gotta find the one that meshes with what you got running.