AIO or Custom WK?

I hate to grave dig here but custom loops are pretty intense to be honest, and if you're not overclocking there really is no benefit versus an AIO. But you do get the benefit of having your GPU on the same loop and that's the only benefit I see in your situation. Why do you need anything more than the stock cooler on the GPU, are you in a desert? Honestly just keep things as they are and maybe buy a h100i v2 for the cpu. You should be just fine.