I'm not sure exactly how I would handle it either. The three options
you suggest are your only options I can think of. So, pros and cons of
each.

Stud wall
Pro - room for mechanicals, easy to wire, can make nice a straight
Con - loss of room at stair winder, will have a funny shelf at
transition (Can be a decorative element though)

Furring Strips
Pro - less loss of room, still able to run electric
Con - can be a pain to get plumb and straight, no room for measurable
insulation (Not a big deal if below grade IMO), more work than studs,
attachment can showcase water issues that maybe were not evident, shelf
created at transition is too small to put anything on.

Glued direct
Pro - fair transition to 1st floor drywall, best maximization of space
Con - no room for electric (Possibly a code issue), moisture, no way to
ensure plumb and straight, could look like crap, still will probably
not line up with upstairs drywall anyway.

So, if it were me - I would do the furring strips IF the wall was
straight and plumb and the basement was very very dry. If there were
any chance of moisture seeping through the block then I would do a stud
wall.