Hi, guy's it's been a while that I've been on-line. I'm still fighting pesky Eldar, but I've changed my list. Can you guy's give me advise and tactics on the pesky guys Thanks! Oh yeah soon I should have a 1500pt army that I'll like help with

DP, wings MOS, Lash of Submission

7 Plague Marines, plasmagun, Champion, power weapon
5 Noise Marines, 5 Sonic Blasters
5 Noise Marines 4 Sonic Blasters, Blastmaster.

Heavy Support
5 Havocs, lascannon, autocannon, 2 missile launchers, champion power weapon
2 Obliterators

The Eldar army is Pheonix Lord (dire avenger)
Farseer fuly kitted
Warp Spiders
Dire Avengers
Small army but used to K-Own my old list

Any tatics and changes would be muched appreciated TA!