The rule of thumb with any EU is the primary material (for Star Wars, the 6 live action films and the Clone Wars tv show) are, along with statements from the head creative person (Lucas in this case) are absolute canon. Everything else can be considered canon until the "main" canon contradicts it. So yeah, episodes VII-IX are probably going to disregard the current EU timeline which will be relegated to an alternate universe at best. Anything from the that can still work without breaking established top tier canon can still be considered soft canon. Darth Bane can easily still exist, because he lived way before any of the films, and KOTOR too for the same reasons. But yeah, Thrawn, Talon Karde, Mara Jade, Jaycen Solo, all that stuff's almost definitely no longer main universe canon.