Well if you think about it, we got the same thing with Palpatine in the 1st trilogy
We dont see him until Empire and even then its only a hologram
When we finally do see him show his power in the force, him skull f**king Luke with his force lightning, he gets blind sided by Vader and thrown into the pit.
The roles are almost paralleled really, aside from their deaths coming at different points in their respective trilogies
So much of the original trilogy is strengthened by the expanded universe and lore around it that has been developed in the 30 years since - eg. Palpatine, who was essentially just OLD EVIL GUY by the end of ROTJ, but now has a rich backstory.
Also some of it has been weakened, like arguably Darth Vader's character as a result of some poor writing in the prequels.
A movie like this can't answer every possible question one might have about the universe. Undoubtedly it will spawn its own extended universe, including Snoke's backstory. Who was he before, what's he been doing for 100 years, why did he only appear after the fall of Palpatine and Vader?
There will be more books, movies, games and tie-ins to piece it all together. Cynically you might think it's a shameless cash grab but almost everyone here will shamelessly devour more Star Wars stories so can't complain too much.
One of the big gripes I'm reading again and again is the bombs dropping in the vacuum of space.
It's just not believable.
However, can suspend belief for the Force, lightsabers, astral projection and a walking talking carpet though.
I know you're being mostly sarcastic, but anyway...
Star Wars has never really been a sci-fi in that the tech and 'magic' systems have no real scientific basis. It's as much a fantasy series as Harry Potter is, just set in space. Very much make it up as they go and don't delve into the details. This works for Star Wars - attempting to retcon a scientific framework around the force (remember midichlorians?) only detracted from it rather than strengthened it. Some things are better left mysterious, including how bombs fall in space. If you dig into the science of their space battles very deeply pretty soon none of it makes much sense.