Since we're getting a deploy mechanic from the YV-666 expansion's Hound's Tooth title + Nashta Pup, do you think this could be hinting at the possible release of the VCX-100 and a Ghost title card for a deployable "Phantom" auxiliary craft in future waves?

Well they'd need to change the name to avoid confusion with the TIE Phantom.
I dunno. I somewhat doubt we'll see Rebels stuff just because...well, my personal feelings. Not a great argument, but I'm entitled to my own thoughts.
Personally I don't really like the Ghost. :/
This has also been discussed to death in other threads

I totally believe this paves the way for a release like this. I think Wave 8 will be all SW:Rebels, with the Ghost, Phantom, Inquisitor's TIE, and the Gozanti-another ship that could use deploy.

Nope.

https://community.fantasyflightgames.com/index.php?/topic/173460-will-the-hounds-tooth-and-nashtah-pup-open-the-door/?p=1584481

Depends a little bit on the actual mechanics of deploying, but it certainly is possible.

If they do introduce the ghost, I hope the miniature tones down the cartoony style a bit.

Nope.

https://community.fantasyflightgames.com/index.php?/topic/173460-will-the-hounds-tooth-and-nashtah-pup-open-the-door/?p=1584481

Except they said this not so long ago, as well:

Right, and that captures none of the tone or body language I witnessed with my own eyes.