Those sequels never stop, do they. And a Terminator movie without Arnie is a wasted time anyway. Thats what the first Terminator movies lived for - Arnie and the Special FX.
Talking about time travel stories. Lately I'm watching a series on Netflix, called "Timeless", may be you heard of it? Its a rather mysterious story about a secret government project that invented a timemachine. Which then gets stolen right away. It only can go to the past (and return), and obviously the rogue time travellers are using it to change the time line and hence the present. Luckily there is a crude prototype time machine, and a team gets send out to mend things and catch the thief.
Obviously they didn't pay attention when watching Star Trek and Stargate, since they all run around killing people and changing events in the past - and accordingly the present has changed every time they return to their lab. At least they don't get blamed, because only they know that thing are not what they are supposed to be any longer. Although each episode is about a certain historical event (the Hindenburg disaster, the Lincoln assassination, the battle of Alamo ect.), the series is more about telling a bigger background story.
Over all, its not bad to watch. It reminds me a bit of the old series "Time Tunnel", if you remember that. Long ago...