Open baffle Needs power?????
Not the ones I have had experience with.
2CE's do not need power contrary to all the talk out there.
They are an easy drive despite the sensitivity.
They have a first order crossover, makes it easy to drive.
Have driven mine with all sorts of amps they sounded good with everything I have thrown at them,. From my present Line Magnetic 211IA 32w valve amp. They even sound better to my ear with this amp in 10 W triode - go figure.
All the way up to a 500 W - 8 Ohm - 1000 W - 4 Ohm. Class D
Did the headroom improve - No!
Not amp fussy at all, the Marantz will do fine till you get the urge to change.
They do however respond to changes in the source very well the better the source, the better they perform every time.
Spend your bucks there far more rewarding.