1 hour ago, DarthDude said:If it will be a 400 page tome like their average SW corerulebook, you'll easily cover the mechanics, skills/talents, a system for supernatural powers AND weapons/gear. In fact if its called magic, biotics, superpowers, weapons or whatever, the mechanics are nearly the same and thus wouldn't take that much space. The spells had qualities in the Runebound GenCon rounds you also find in weapons. If you have an universial set of (positive and negative) qualities, you can simulate absolutely anything. Open Legend does exactly this in just 140 pages (including vehicles, gears, etc) quite well. So I somehow doubt FFG won't be able to achive the same in thrice as many pages.
Honestly, if they publish a generic corerulebook, which would be virtually useless without splatbooks, it would be disappointing. Sure, there will be splatbooks to offer additional options and more depth, but the necessary stuff should be expected in the corerulebook.
And to properly develop a setting your going to need chapters on history, cultures and species, maps and geography (or Astrography), current events, major organizations and NPCs, guides on the types of adventures that can be had, possibly sections covering specialized equipment, in addition to whatever mechanical tweaks the system requires for a given setting.
Generally speaking your going to need 400 pages just to cover a single setting well enough that the GM doesn't need to do a major amount of world building before he even gets to adventure design.