You're Daemons, what do you care about
MEQ? You have Daemonettes and Vector Strikes, Marine's aren't a problem. Now mass Firewarriors/Kroot with an Etherial (pulse bomb is super good), hordes in general, and Eldar pseudo rending, those are issues. Torrent Grinders eat them up. Plus you can use the Slaneesh Grinder to generate cover saves for the Nurgle Grinder, they're an awesome pair.
It is currently unknown if the rending transfers over (same for the Lash Prince), most play it as if it does not, but
YMMV.
Hounds and Seekers are both awesome,
imo. I prefer Hounds for the t1/t2 assault (rather than t2/t3 of Seekers) and the durability. But both have their place. To plug myself, here is my 1500 pt list in action (and a good example of the value of Hounds and Daemonettes).
http://www.frontlinegaming.org/2013/08/02/guest-editorial-a-tool-for-every-task-or-why-you-need-to-know-your-opponents-army-a-battle-vignette/
Lords of Change are awesome, not debating that. You're not wrong to run 2, I just prefer having access to more psychic trees (and the Lash is amazing anti flier)