So, Alan and I played a 2000 point game of Daemons vs High Elves. He was using his "caledor list"
Archmage on Moon Dragon
15 white lions
6 Dragon Princes
1 Bolt thrower
I decided to try out (proxying) a pure Slaanesh force.
Daemon Prince (lvl 2)
Mounted Herald (lvl 1)
Herald BSB (lvl 1)
Herald (lvl 1)
5 Seekers of Slaanesh
My strategy was to go up the center/left flank of the board while my seekers reeked havoc from behind his lines. They moved up quick and subsequently got into combat with his archmage on the dragon. I managed to kill his archmage but it was the dragon that whittled down the unit with combat res, as he had the flank and outnumber.
On the left side of the board, I was utterly destroying his Dragon Princes, bad rolling on his part meant that he only killed one of my daemonettes out of a unit of 25. I killed 3 of his in the next combat making him run and running him down. I then destroyed a unit of 10 spearmen, then a second unit of 10 spearmen, before hitting the bolt thrower and destroying that.
In the center of the board white lions destroyed my other unit of daemonettes, but they still put up a fight, taking out 5 models and a dragon on their way.
You'll notice the Daemon prince wasn't mentioned. This is because he died on turn 2. All he did was get off the lore of Slaanesh spell that makes all enemies roll 3d6 for leadership. This really screwed up the High Elf plans of charging when they couldn't pass their fear test!
One unit was made stupid which also hindered it quite a bit and both dragons were rendered stupid after their riders died. Overall, it was a good game. It turned out to be a draw in my favor and I learned a lot.
Things I learned:
Daemon Princes are not worth it as a lord choice.
Always always always, if you have a unit of daemons, put in the herald for that unit.
Pure god armies may be thematic and neat looking, but they won't have the staying power of a mixed list. (the example I thought of is my S3 Daemonettes hitting a Brettonian or Empire knight line. There would be nothing I could do against the 1+ and 2+ armor saves, regardless of if I went first.)
Khorne and Slaanesh seems to be the way to go on ability and on cost.
I'm going to be looking at getting some more games in and seeing how they go, running a mixed Khorne and Slaanesh list as well as starting to build and paint the daemon models I have.