I like S&A and I dont think that it needs improvement.
I had been quite succesful in SP games with following scales:
Turmoil:1
Sloth:2
Temp:0
Growth:3
Luck:3
Magic:3
Watch Tower,Dominion 5.
Ghost King 2W,3E,4D.
My approach seems to be exactly in between Boron`s and Rabe`s
Goal is to rely completely on summoned troops/battle mage armies as fast as possible.
S&A seems to fit very well for such a tactic:
-you have several nice starting summoning spells
-you have extremely good site search abilities
-you have very strong battle mages
-you have good research right from the start,if you only recruit national mages,no troops.
For initial expansion,I have my Ghost King SC,who, if played correctly,is very strong in conquering Indie provinces(indie strength 6 or 7),starting with it at turn 3.
I didnt play a MP game with this yet though.
I guess on a crowded map,I could have difficulties if I encounter a nation with strong national troops at the start,who is able to deal with my Breath of Winter Ghost King,e.g. Jotunheim,before I get my summonings rolling.