I think it's quite balanced - things such as changing the drugs around (more streamlined and archon cant choose diffrent ones every round of CC) making certain wargear more costly, increasing warrior costs and reducing special weapons for small squads balances them well. Reavers becoming cheaper but making there armour save and strength weaker etc...
In the end most lists still have the ability to stay fairly similar to what they are now, though with all the new things I wouldn't want to.
An good exmple of balancing is this:
Old codex - 10 Incubi - 250pts, 10 man Raider Squad (with sybarite poison blades, splinter cannon and blaster) 161pts. Total 441pts
New codex - 10 Incubi -220pts, 10 man raider squad (with the same as the above) 190pts. Total 410pts
As you can see from the example above the balancing act has worked well, in that yes my Incubi are cheaper but my scoring units have gotten more expensive and are still as fragile as before.
Now before anyone say they now have the Power from Oain rule - yes I know they do but those 10 men have to kill a squad first and for them to gain it, so it has to be a fairly small squad or a massivley injured squad to do so in most cases which would leave them out in the field unprotected to be smashed by large amounts of fire.