The Ghost King

[Micah]

His versatility makes up for it about the time you cloud trapeze him on top of one of your opponent's armies and wipe it off the face of the earth. That's worth a 1-turn loss in expansion. The cyclops and wyrm generally don't end up with that kind of mobility. =)

I actually usually manage to use him to solo indies naked by choosing the weak provinces and have my national scout meet him with some armor a few turns later instead of losing a turn if I can't forge on turn 1. This will result in the occasional unlucky hit, but them's the breaks.

I'd also recommend that you take at least E2 with a GK to pick up summon earth power and then invulnerability (reinvig is important to get rid of the fatigue you take while buffing, strive to keep your fatigue score under 30 when engaged), E1 is a huge waste given how few points it takes for the much better E2. Nature is also not great to take in small quantities because the fatigue hit for personal regen is pretty huge (40 points!) which will generally get you killed.

[Wrana]

Agree with Cleveland and Micah. Though I would prefer him asleep and pick up speed after Construction or Alteration is researched (but just maybe Black Steel Plate could be enough at the start).
Considering paths I would avoid Astral unless there's absolutely no other way to get it... but usually there is. Nature may be good but will require N4, which would also give bless (if your sacreds would benefit from such) + the above-mentioned E2+. What is beautiful he can actually pull that off if asleep.
I also agree that Cold Dominion gives him an edge - so he can be better for nations which are Cold-preferring. But this is a minor consideration.
Considering a Growth - it's easy! You just say that he's an ancient Druid leader or former sacrificial Fertility king!