Just my opinion RE: Snoke

In the Original Trilogy we knew bugger all about the Emperor. We never knew that his name was Palpatine. The term "Sith" was never used either. All we knew about the Emperor was:
* He was strong in the Dark Side of the Force and has special powers
* He had seduced Anakin into the Dark Side
* He was the head of the Empire and Vader's boss
...that's pretty much it! We knew nothing else about him. In TESB he appears as a hologram speaking to Vader, then in ROTJ he mostly skulks about before being chucked down a hole by an amputee Vader.

Darth Maul was someone who got everyone super excited when trailers of The Phantom Menace came out. Yet he got hardly any dialogue, limited screen time and again, we know practically nothing about him. All we know is that:
* He's Darth Sidious' Sith apprentice
...that's about it! His species (Zabrak) is never named, nor are the history of his tattoos or how he became a Sith blah blah blah Dathomir yada yada yada Nightsisters bleh. As far as the film was concerned, he was just some scary looking dude with pro sabre skills.

So what do we know about Snoke?
* He's a strong user of the Dark Side of the Force
* Kylo Ren is his apprentice
* He's the Supreme Leader of the First Order and has special powers
That's honestly about as much as we knew about the Emperor in the Original Trilogy. Did we need to know any more about the Emperor? I mean, if you sat down and watched the OT without reading any books, watching any TV shows or the Prequel films etc. - i.e. if you just watched those movies on their own... they don't suffer from not knowing who the hell the Emperor is.

Similarly I don't think that the Sequels really suffer from not knowing Snoke's background too. We don't need to know everyone's back stories. The movie should really focus on the main protagonist's journey -- in the OT it was Luke Skywalker, and in the ST it's Rey. Yes, I understand that this journey really isn't done as well as in the OT with too many side quests and issues with pacing etc., but pausing the narrative to tell more side stories doesn't help. This was the issue with things like the Casino Planet and Finn <3 Rose -- they're distracting side stories that could be either shortened or just omitted from the film. Same with Jar Jar Binks... all these distracting antics.

Stories like these are better left for expanded canon like books, comics etc.