Problem is does Disney care enough about those properties to continue them (and chances are extremely high they don't, outside of Deadpool there really is no money to be had in any of the other R franchises they've acquired). Deadpool is one thing considering how much traction it has and how much notoriety it has. Predator hasn't had a good movie since the first one honestly (and to top it off not many people even know the Predator franchise) and not many people outside of die hard sci-fi fans even has a clue of what the Alien franchise is (and lets face it the last two so called Alien movies weren't exactly well loved). As far as Disney is concerned it has the rights, doesn't mean they have to use them (they could just license the rights out to other studios to make movies). Iger pretty much said he's open to Deadpool staying R because they could pretty much use it as a staging point to start an R-rated MCU that has nothing to do with the current kid friendly MCU. As far as I understand it the Marvel TV shows aren't overseen by Marvel Studios outside of their place in the MCU (which they are part of). Full creative control seems to be with whatever network/streaming service is releasing the shows. You also have to consider the shows aren't carrying the Disney name and while the Marvel tag is still there not many people associate the shows with the MCU or whats currently going on in the movies. I could be wrong considering I have no interest in any of them but that was my understanding of how things have been working.
The Terminator rights fully revert back to Cameron in 2019 so I don't think Disney will take the risk of releasing a new one (and Cameron has plenty of ideas for the franchise and it sounds like it's going to either be a hard reboot or he's going to completely write out anything that happened after 2) and considering how universally panned every movie after 2 was I highly doubt Disney wants to touch this franchise with a 10ft pole.
I don't doubt that they'll continue a lot of the franchises they have but I can about guarantee you they will not stay R. Considering what you can get away with now in the PG-13 category I'm pretty sure most, if not all, of said franchises will fall into that category (again the only exception being Deadpool). Honestly all Disney wants is the money these can bring in, I mean look at how quickly they jumped on the chance to buy Star Wars from Lucas. Guaranteed money maker and they knew it and now they're squeezing it for everything it can give (and more).