I've cut some hard counters and made room for Unsubstantiate and it's been great for the deck. I'll post my current list tonight, it's actually extremely effective against vehicles and if I had been testing it harder earlier, I probably would've brought it to the tournament.
I think Linvala is too slow and clunky and doesn't pay off nearly as much as you'd like a singleton bomb to pay off.
I said this months ago when KLD came out and everyone was trying to find ways to make it less susceptible to vehicle decks.....Everyone seemed to ignore it...
The early tempo hit from bouncing or pseudo-countering a T2-T3 play can make a big difference in getting over the hump to turn on our more expensive counterspells and sweepers. Watching an opponent tap a creature to pilot a vehicle just to have the vehicle bounced can be a pretty significant tempo hit.
The bounce effect is still relevant as token removal. It is also good against creatures that use +1/+1 counters, which are pretty common with all of the different varieties of Energy and Constrictor decks running around. Isn't terrible against combat tricks and Auras/Equipment either, although that is significantly less relevant on a tournament level.
Bouncing your own creatures to dodge removal is definitely relevant. Bouncing your own Blue Gearhulk is just gravy (EoT Flash Gearhulk, Flashback removal to kill something, swing for 5, EoT bounce Gearhulk, Flash Gearhulk, Flashback removal to kill something else, swing for 5).
I also found that the bounce pairs up nicely with
Blessed Alliance, helping to work around the usual sac weakness. Being able to bounce your opponents little critter to force them into saccing their bigger threat can be very helpful. Same is true if you decide to go the route of
Oath of Liliana.
Being an Instant to grab back with Baby Jace or Blue Gearhulk doesn't hurt either, same if you plan on trying to go the
Dynavolt Tower or
Thing in the Ice route.