First off, let me start by saying that I'm not claiming that
anything of this is 100% accurate or confirmed. I know how much people are skeptical towards "My friend told me..."-posts, so I'm just going to share this and let you speculate about it.
This is my first time on reddit(as a poster), so I hope this turns out right.
Who is my source?
A longtime friend(yeah...) of mine is a concept artist and is currently working/have done work on Episode VIII. He worked on Episode VII as well. I wish I had a "better" answer.
Where is the evidence?
There is none. This comes from a Skype phone conversation since he's resident in Europe, and I'm in the U.S. I'm just sharing as much as I can remember.
Some of the rumours listed below have already been reported/speculated about. It's not a lot at the moment, might become more later.
Some of these are to be considered
spoilers, but like I said, they're rumours so it's up to you.
Here it is:
- The film does NOT have an official title as of yet.
- This film will "feel" more like the prequels in terms of world-building, including several new planets.
- Expect to see more strange creatures and droids than in any previous film in the saga.
- Kylo Ren is unmasked, unclear if he'll have a new mask at some point. Also, he has a rebuilt lightsaber similiar to the one in Episode VII.
- LOTS of concept arts of large-scale battles between The Resistance and The First Order.
- General Hux has the same outfit as in Episode VII. Might only have a very small role.
- Luke has the same outfit as in Episode VII. Doubtful that he will leave the planet of Ach-To in this film.
- Rey's new primary weapon is Luke's old lightsaber.
- Yoda has an appearance in the film(on-screen).
- Captain Phasma is seen standing amongst a large group of dead soldiers(probably resistance fighters).
but it is what it is.
I suppose we'll see a young Lando in that movie tho
would make a pretty good flick. 
Are you comparing it to Luke rebelling against Yoda
At having to spoilertag so the sissies won't complain