I'm not so sure about that.
Historically, lock support just hasn't been a strong replacement for self served double mods. I'm wary about assuming a ship with the Eta-2's intended role, statline and pilots will be fine if you have to bring a whole extra ship to provide the re-rolls.
Tarkin especially I'm really not sure on, he's System Phase, requires Tarkin himself to have taken a lock the previous round (which he only gets at I3!) and requires the target he locked to have ended the last turn at range 1. That's so many restrictions, so much of the order of play that has to go right. Compare that with Dutch, who gets to just pass a lock at I4. And Dutch still isn't great ace support. I know Wedge isn't technically an ace, but who would you rather have supporting him? Jake Farrell or Dutch Vander? One of those combinations has made it to a Worlds final.... The point is, I5 and I6 ships tend to want to be locking themselves because they have the best chance of getting the locks when they need them. Also, think about the days before B-Wing s-foils. Who was better, Ten Numb with Dutch Vander around to give him locks for re-rolls and double mods? Or Braylen Stramm getting them by himself? Like, it's not even close.
As for Synchronized Console, we don't even know if the Eta-2 is getting the modification slot. I actually suspect it won't. Seems in line with how tiny the ship is. Also, consider this. If the Eta-2 has a mod slot, what's to stop you just putting Targeting Computer on the Eta-2 to give it a white lock and bypass the purple? 3 points is way, way cheaper than a whole support ship.
Again, this is all points dependent. If the Eta-2 is cheap enough that you can involve one or two high I aces, a support ship and maybe a flanker or blocker then it's probably fine. But if it's costed, as I suspect it will be, not far behind the Delta-7, Fang or other strong ace ship then it's probably going to be the domain of three ship lists. And three ship lists don't tend to like a whole third of the list being given over to support.
You're right about the white evade, though. Eta-2s are basically Precog TAPs, and they've demonstrated how scary they are. Again, points dependent though. If the Eta-2 is expensive enough that it's a focal point of the list, I'm cool with it playing hyper defensively - if it's doing that, it's offence is going to be terrible. It might be a hard to kill ship, but a hard to kill ship that does no damage is easy to ignore.