[Kobal2]

If you take a temp scale, take cold, not heat. At least if you have misfortune. Misfortune and Heat burn your labs a lot. Also cold will help with your water elementals, and doesn't affect the income of any underwater province you might score.

I wouldn't say you need super high production - the samurai are higher resource than average but they're not Ulmish black plates either. 1 or 0 is quite enough, you can always compensate by having more castles (even if those castles don't have labs or temples - a ninja castle is not the worst thing to have)

I'm not sure the Lich is all that great, because it won't get you into the water any easier whereas a tough bloke like the Lord of Plenty can even with just Const-0 items and some token Alteration research (Boots of the Behemoth, Ring of Poison Protection, Ring of Water Breathing, any helmet. Script Body Ethereal, Ironskin, Personal Luck, hold, hold, attack. At Const 2 he gets a Midget Masher or Gloves of the Gladiator instead, freeing his feet for Birch Boots).
As long as you keep him away from trolls, and possibly Ichtyids as well (nets always scare me), he should be able to stomp just about anything while always being one Returning away from home.