I really like the Spellscar Mystery, if you mostly ignore the bits that rely on the Primal Magic events table.
I recently theory-crafted a pretty effective character focused on dispelling using the Spellscar mystery (search my posts for an example if you're interested).
Personally I'd see the bonus spell list as mostly green, some good options here.
The added class skills are blue (UMD!)
Animate Primal forces: Green/blue (standard action makes this ability worthwhile).
Eldritch Bolt: Orange/green (Force damage at least, but it's never going to do lots of damage. Good choice for low level though.)
Eldritch Resistance: Green (solid choice but nothing fantastic)
Eldritch Scar: Red (Too few uses, far too random in what can happen. Excellent for RP reasons or in certain campaigns I guess.)
Magic Penetration: Solid BLUE (A really good way of raising the effectiveness of dispel magic, combine with feats like Dispel Synergy or Destructive Dispel)
Mystic Null: Blue (no nonsense insight boost to saves, whats not to like!)
Primal Manipulation: Orange. (Its a very good ability, hampered by the spell list of an Oracle. If your entire build is focused around being a blaster this could maybe go to Blue)
Primal Mastery: Orange. (Re-rolls are good, unfortunately I just don't think the Primal Magic stuff provides enough benefit to base a build around.)
Trigger Primal Magic Event: Orange. (See above re. Primal magic events. If you are basing an entire build around this in a campaign heavy on Primal Magic this is obviously a BLUE choice).
Spell Resistance: Green. (Not the best SR, but its a solid choice).
Final Revelation: Orange. Again relies upon the Primal Magic event table which I just think is too random to rely on.
Spellscar mystery works well if you want to focus on dispelling followed by a SoS or SoD spell. A blaster type might also work (although will be hampered by the Oracle spell table).
I think it would be hilarious to play a character who uses the Primal Magic event table, but I'm not sure the rest of the adventuring party would find it quite so amusing when you summon a horde of multi-coloured centipedes that you can't control onto the battlefield!
Just my 2 cents....
