Yes, this. I was pretty excited with the idea of KotFE when it was announced. Sounded so cool. After the fourth chapter, I unsubbed until about a week ago, to let all the content come.
The drips and drabs of content thing is definitely not for me, I hated that. A lot.
I've now re-upped and finished playing through KotFE and KotET with my Agent. For the most part I have enjoyed it
greatly and call it good fun. I understand now that it's somewhat different for a Force-using character, so I am going to do it with one of the Jedi now (though I understand that what side you came from makes little difference, but hey.)
After that, however... I really just want to skip KotFE and KotET with all my other characters. I don't see a lot of replayability here, and there are some pretty tedious stretches (read: chapters) that I certainly won't want to do more than twice.
So, yes - mark me firmly in favour of future content going back to multiple storylines for the different sides, and ideally for different classes. I don't even care if expansion X is for class A and expansion Z for class B. I loved - almost - all of the classes (Smuggler is the weakest story by orders of magnitude and I haven't got the gumption to finish it just yet). New content as an excuse to focus on a character would suit me just fine.