I would like to see Dire Avengers cost 350 requisition, but give slight buffs to banshees and/or dark repears (slightly reduced tear-down time) to compensate. Rangers should cost 15 power (I've been saying this for ages but I don't think it's any less true). DA seem just a tad too efficient in the opening stages. OFC, they scale off as the game goes on - but the trade off od going heavy T1 Spam is the heavy map control (and thus, easy tech) one can achieve.
DA are a prety efficient unit with their 35 range now, fast movement speed, and dope grenade doctrine (also ubiquitously taken). To reduce the reliance of players spamming DA's into fast tech (kinda like the original patch only this version is more counterable), Eldar players, like Orks and SM, should need to diversify their army choices to have efficient map control.
With the price increase to DA, I think it will not only represent their power better, but also encourage Eldar players to use their Aspect portal units or rely on upgrades faster.
** OFC, if power generators weren't so friggn' easy to place about the map and didn't provide such a massive power income, the opening spam wouldn't be so strong **
Personally, I'd rather see changes to power generators than trying to keep balancing over-efficient units/elites. It wouldn't be such an issue for some units to have a strong opening (first 5 min) presence if it wasn't so easy to tech and punish players for losing map control.