So it's been 4 years, what ROM brings the definitive experience?

So this phone is about to turn 4 years old, there have been great ROMs, mods, kernels, etc. and I still have that one question:

Which ROM/Kernel combination brings the best and to put it straight "DEFINITIVE" experience?

I know it all comes down to preferences, what ROM gives you the personalization that you want and what not, but as someone who has only tried 1 ROM and stuck to it, I'd like to know everybody's opinion.

I've been using Carbon ROM and it has been a GREAT experience, but after a while you get bored of it. I've seen this device is getting some Lollipop love, but I think since this device can only do so much, you won't get the full Lollipop experience, or that's what I think at least, has anybody tested out the Lollipop ROMS for this device fully?

I've got some weird cm kernel I don't even remember where I got from (I've heard great things about wildkernel, is it any good)

Well anyway, I just wanted to know everyone's experience and opinion on what the definitive, MUST go to ROM/Kernel combination is that will make your cellphone the best in terms of performance, style and battery optimizer based on said experiences :)