I think the balance still isn't there. I think normal difficulty has become way too easy. Not just because I know how to play, but because the SK is not a threat at all.

He hardly ever attacks my cities, hardly ever attacks the shards, NEVER casts spells in combat, and is basically simply a mouthpiece at this point, i.e. all bark and little-to-no bite. 

Each city I build should automatically generate threat, regardless of difficulty level. Every 4-5 outposts should generate threat. Each threat level should moderately increase the chances that I'll see SK troops in my cities, or on my shards. Make outposts attachable and give them hit points similar to shards. That way they're not easily destroyed, but not too cheesy.

Does the Sorcerer King even cast spells? My new hard difficulty game is nearly complete and I haven't seen him cast a single spell. I thought maybe it was a difficulty level thing, but no dice. Even hard difficulty does little to make me feel like the SK is much of a threat. 

A few builds ago, the SK felt like a threat (perhaps too much). Now he feels like a nuisance at his worst. Please consider making him feel more oppressive and all that. Hell, in my current LP, the SK hasn't built a SINGLE outpost and there are plenty places for him to do so.