So depends what you are looking to get out of it. Looking for an easy competitive list go akhelian, mostly eels. Looking for fun, narrative, or meta breaking go namarti. Ive ran a double eidolon, namarti corps list and while a blast to play i think i won 2 out of 10 games. However switched to an 18 eel list, turtle, eidolon, and akhelian king list and haven't lost yet in my local group. Granted i only started the list i am 5 for 5 against nighthaunt, new flesh eaters, and stormcast. So just depends what you are looking for and play style.