Curious how the fanbase feel about this

It depends on whether or not Dick Grayson's hiatus from being Nightwing is permanent, if it's only going to be 2-3 years of Dick Grayson not being Nightwing, then we don't need one.

If it is a permanent change, then sure, I think that someone taking over the Nightwing mantle will only enhance the importance of Dick Grayson's legacy as Nightwing.

In terms of who, well my choice would be Damian Wayne when (not if) he comes back into the DCU. There are several reasons why but the main reason is that Damian Wayne was probably closer to Dick Grayson than any other member of the Batfamily (even more so than his actual father Bruce), they formed a really tight brotherly bond. Dick Grayson was Damian's first mentor and Damian was Dick Grayson's first sidekick. I would argue that Damian was at his best when paired up with Grayson. I can totally see a scenario where Damian comes back and finds out that Dick Grayson is "dead" and then out of anger, he runs away from Bruce (because he feels as though Bruce failed both him and Dick) and becomes the new Nightwing in order to honor his "fallen" brother. Sort of like Superior Spider-Man, Damian would have his own take on the mantle, trying to be more effective at being Nightwing than his predecessor, I mean, he already had that philosophy while he was Robin.

I feel like Damian is way to young to be Nightwing and he will probably become Robin when he returns.

Only if it is temporarily. For me there is just one peron who can be Nightwing and that is Dick. It's impossible for me to imagine someone else for the role therefore I would dislike a permanent replacement a lot but Dick is just on a mission for Batman so he should be back soon maybe after 10 issues or 20? I think 20 is too much maybe 15.

I would like to see Cassandra back so maybe she would be a possible choice but on the other hand I'm not really sure if she would fit the role. Another way would be to create a whole new version of "Nightwing" maybe Supergirl, a Nightwing with superpowers could be interesting (don't know if necessary but interesting) but I'm not sure what's going on on her own comic so I don't know if that would be possible.

Oh and btw. I also think that Damian is too young but if he was older I think he would be a good choice too (maybe because I'm a big fan of his relationship with Dick).

No, Dick should really be the only one who holds the Nightwing mantle.

Nah, that's Dick's thing. It's not exactly a legacy mantle to be taken up or anything. Any other character can come up with their own name (like Bluebird).

Don't see why not

I'd say no. Let Dick resume the name in a few years, either continuing his spy genre (if successful) or resuming superhero/vigilante role (if the spy thing tanks).

But, lets say that there had to be a new Nightwing, my picks, in order, would be the following:

1. Damian Wayne- He has the strongest connection to Dick, so seeing him wearing the black and Blue (or red) would be a sweet recognition of that. Also, he took the role in Injustice. So. Precedent I guess.
2. Babs Gordon- Batgirl, just as much as a Robin, has always felt like a junior level hero's name. Batgirl sounds young and not mature, and she sounds like she is operating under Batman's permission. Babs deserves a more independent and dignified role. She also has, arguably, a stronger new 52 connection to Dick than even Damian. Plus, she was/is Nightwing in the Smallville comics. So. Precedence I guess.
3. Steph Brown- Spoiler is a decent name, and she has her own look, so she doesn't need to take over Nightwing. The only reason I'd be okay with it is that they are the two "light and bright" members of the Bat-comics.
4. Cass Cain- I subjectively think she's neat, and she needs a name that DC can put on the cover of a comic (which I hear there are legal problems with black bat). But thats totally a subjective thing.