in DOW 1 farseer with some upgrades got "Eldritch storm" which practically wipe out an entire base lol.. At any rate you need to mix your troops. Rangers are MUST, stealth + reinforced they will break morale for any morale using squads. Banshees needs the upgrade from the soul shrine upgrade building then they kick ass, also they get aoe attack which breaks morale as well. But mostly I used them for tying up melee squads. Dark Reapers are your cannon team, have one fully upgraded it will shred anything in range. So in the start of the game u build one of each squad and attach the Farseer (which got passive aoe in melee) to the banshee. Then near each LP you build you also add Webway gate with passive "Shroud" which make all buildings invisible and the aoe heal passive upgrade. no matter where on the map the enemy strikes you can pop out of the webway and use your meager 3-4 squads to annihilate enemies which were not expecting you. Also you can do trial&Error and build a gate behind\inside your enemy main base and relocate into his base 6 turrets at the same time for max troll and then charge through the gate with your ninja team. If you want truly max dakka with eldar on DOW1 you want 3 squads of warp spiders as this guys teleport around, got anti armor 'nades and shred stuff with their guns... just pop in shot and run away. Once you got an avatar and fire prism it's just attack move and sit back as they will shred anything in their path. I'm not expert on DOW2 but mostly from what I remember in skirmish you used guardian squads or heavy support weaponry with banshees and did lots of kiting or "X" run away... didn't liked DOW2 skirmish maps much they were so different from DOW1 I really didn't liked them. on the campaign I had lots of fun with the Eldar (retribution), instead of the warlock you deploy Wraithguard honor squad and then they guets buffed, upgrade them to passive healz and AOE ranged attacks and it's a win on highest difficulty no brainer. But mostly Eldar are cool because they are specialized "immortal" high tech race which is also cunning and snobsih at same levels. So playing with them it's like being space dick and be good in that role.