Aliens in the new films

[Solid Snack]

It seems that in the PT, apart from mostly CG aliens like the Gungans, Geonosians etc. they largely stuck with the OT aliens with some minor cosmetic alterations. Rodians-the species to which Greedo belongs-were practically everywhere in the films (including as Anakin's friend Wald played by Warwick Davis), as were Twi'leks, the twin-head tailed aliens seen in Jabba's palace in Return of the Jedi (Aayla Secura being the most visible, although they were many background ones-Lucas's daughters even got in on it). Several other OT aliens appeared, and even the Neimodians, when CG proved too costly, were realized as what pretty much looks like a slightly updated version of those arguing aliens (Duros) in the cantina.

Force Awakens however, mainly featured all-new aliens, with the exception of Chewbacca and some returning rebel alliance characters, and one or two characters that sort of resembled the Ithorians (Hammerheads) or Snaggletooth. Rogue One seems to be sort of continuing the trend, although apparentally we'll see at least one Mon Calamari.

So should we see some familiar aliens, or continue to have new ones?

 

[Reverend]

^Why can't we have both? Both is good. It's a big galaxy after all and we probably haven't even seen 1% of the diverse sentient species out there.

Also, I'd dispute that the aliens introduced in the prequels were "mostly CG". Aside from the prominent examples you stated, most of them were in point of fact portrayed as either physical puppets or make-up effects. The Jedi Council scene alone features at least nine brand new species, all of them either actors or puppets. The senate scene probably doubles that and there's a few more in the scenes on Tatooine, including at least one pod racer that was a puppet. And that's just TPM. Each prequel introduce several new species, most of which were not actually CG, but background extras in make-up. The Couruscant street/club scene & diner customers, the refugee ship from AotC all leap to mind as does the opera scene in RotS.

Indeed, every new planet visited in the PT featured new aliens. The only places we really saw old ones (not counting humans, for obvious reasons) were on Tatooine -- which we've been to before -- and Coruscant which for again *very* obvious reasons must have as diverse a population or species as possible, including many we've seen before. Naboo, Kameno, Geonosis, Utapau & Mustafar all featured new aliens.

So why not so much in TFA? Well, have we ever seen Jakku or Takodana before? No? That's why.

 

[The Wormhole]

Rogue One seems to be sort of continuing the trend, although apparentally we'll see at least one Mon Calamari.

There were some leaked photos months back which indicated there will be a few more aliens from the OT in Rogue One.