My comments on the changes:
1) Scorpion: The Scorpion does not have the same weapon as the Phatom pulsar in WH 40k, no reason to give it to him here. I would agree with SG's proposition, though Ulrik odds calculations showed that 3x 3+ was more in line with its original stats. Considering the change in price for multiples, I would be more confortable with this change first.
A consequence of this change is the relative lack of utility of Fire Prisms. At 2 Scorpions for 450, I dont really see the point of 6 Fire Prisms at 400. In any case, Fire prisms are a tad overpriced atm. In order to keep internal balance, while giving utility to Fire prisms, why not give them 75 cm range. This would be in line with their fulff description where they have double the range of Falcons on the Prism cannon (+ if the IG can do it, why not Eldar?), and given them the utility they deserve in comparison with the shorter ranged Scorpion.
2) The Cobra. EUK has kept full IC for awhile now, and I have yet to see a positive tournament result with a list that fields them. I agree with the full IC change, but I feel the Cobra needs something more. At one point a special rule stating that Cobra cannon should always use Infantry to hit values was suggested. I think that would be good. Or my proposal in another thread to increase trange at 45 cm.
3) Reduced costs for multiple EoVs. I am still unsure about this because of the internal balance issues it poses. If we can fix the relative usefulness of the Fire Prisms and Phantom titan, then I would be in favour of it.
4) Hornets. Firstly I think that they should be able to garrison. This would give them a real niche in the Saim-Hann army. Concerning the weapon load-out and the relative pricing, I think E&C stats and price are balanced, having tried them, even when garrisoning. But the change in weapons would also be ok. 6 Garrisoning Hornets with twin Bright Lances at 250 points is actually more dangerous imho than E&C's proposition.
5) As stated in another thread, the relative power of the TPF is due to the underpowered Pulsar. Eldar Titan Battle weapons are meant to be 1,5-2 times better than imperial Battle titan wepons, due to the fact that Eldar Titan are more fragile, more expensive, and only have two Battle titan weapon mounts. The proposed change as is will only further enbcourage players to play the Assault version of the titans as thats the only place where the extra FF attacks will impact. And that will further bias the list picks towards the Warlock, as he is undeniably better in assault than a Phantom. In other words this only increases the problem, does not resolve it.
6) Concerning the Spear of Khaine, I don't think the Ulthwe Avatar should better than BT. That it would have a little something is fine with me but BT's court of the young king is supposed to be MOAR BETTAR than other Craftworld Avatars. That it would be free I am all in favour of, for the obvious modelling concerns.
7) Exarchs. Something should be done for internal balance, most notably making CC options more attracative (which would perhaps solve the residual banshee problem).

Wraithguard are a bit too strong, especially in the mass Iyanden list at initiative 1. I would be in favour a rubric-like rule to make them less mobile, and the spiritseer add-on should be perhaps rethought to simply adding farsight to the formation.
9) I have other comments on the different lists but they are more list specific than general stats. Perhaps a thread should be started for each list?