Ok I wanted to test the list again so I took it out for a second game. I played against a buddy in Stockholm.
I met a reaver based Codex Marine list. There report can be found
here.
Of the new units, I tested Triarch praetorians, stalkers, ghost arks and the vault. I don't think anything with them tended to be over the top. The game felt even up until turn 3 were it turned fast downhill for the marines. I used the traditional tactic of ignoring the titan, not a single shot was fired against it.
The Tesseract Vault was killed before it could do anything so the game didn't really give any info on it.
One thing that I thought about post game is the ability of the monolith eternity gate-portal to be used to "suck up" a formation on the board and let it reenter directly.
This together with no phasing out really lessens the need for portals to relocate your troops. Freeing up points for other formations. I lost 3 portals very early in the game, but still didn't really have any problems throughout the game.
What it also does is it lets formations on the board relocate and engage directly more easily than before. One could relocate with the old portal as well, it's just that you needed a second portal close to the formations first position to exit the table. So I'm not sure if it's a bonus over the old portals.
It does underline my point above though that it lessens the need for portals.
I think it's probably ok, most rule changes have been nerfs to necron special rules. I clearly wouldn't have lost my Immortal BTS for instance if I would have played with phase out. A possibility I see is limiting the range to perhaps 60 cm. That way you can't at least relocate over the entire board. It might be to limiting. The list needs more testing, before I'd like to do any change.