Agree sound quality better per dollar for monitor speakers all things being equal. Problem is, if just starting out, usually need good stands too - which run between $200 and $400. That's why I suggested floor standers at first.
Also, good monitors are often current monsters, but with the NAD C372 that should not be an issue.
Below is a list of monitor speakers from a previous thread to consider that should leave money for stands:
Quad 12L - well rounded and smooth sound
Quad 11L - if you can't afford their big brother
Totem Rainmaker - imaging kings
B&W 685 - front firing and good value
B&W CM1 - little speakers, big sound, and sound good next to wall
Era Design 5 - not quite up there with the B&W CM1, but what a beautiful cabinet!
Dynaudio Audience 42 - well rounded but like a lot of current
Usher S-520 - if you like the way they sound and look, a great bargain
For Rock, Dynaudio Audience 52 (used) would provide stronger bass
Idea of adding a sub later is a good one and would apply equally to most of the little floor standers, especially the Ohm Walsh Micro Tower, Totem Arro and Magnepan MMG.