The impression that I got from the OP is that Bev (or another love) should have been the imaginary wife in the movie as is.
Ok, I suppose the OP's question was if anybody found it odd that it was a generic wife as opposed to an established past/possible love.
In the movie as is, any past love from TNG could have been used to the same effect (fans would have got it, not fans would not have known or cared - much like Rebecca Romjin's cameo in X-men: First Class). It was obviously a decision that was taken deliberately. If they'd used Beverley, then I think some additional/altered scenes would have been needed.
The scene with Troi could have worked, although it would have stolen pretty much Troi's only significant scene.