I think they'll squeeze out a DLC character sometime this year. Courses would take too much dev time considering they're probably working on the (new) courses for the next game right now. I predict Minna 6 in Nov/Dec and HSG/EG 6 Mar/Apr next year. I think that's the typical Clap Hanz timetable, and that conforms with their roughly three year gaps between releases. The new game will have all of the current courses and characters and roughly double that with new content (so 6-8 new courses). Plus a combined world server like OT2 (and, of course, PS trophies). Those are my predictions.

But yeah, I think a DLC character is more likely to happen first this year.