The usual rule of thumbs here are these
Good INTs usually have better 2 ch sound than do likewise priced receivers. The receivers have greater flexibility. For a second or third system, or a very very, first, I normally opt for a receiver. Especially if its a budget system. It accepts far more input types, digital and analog, and enables you to grow pretty easily . Into a separate two ch or into a multi ch HT system.
The other matching aspect is that the spakers themselves, dictate the power needs. Under 1500 cu ft. is a small ish room. Lots of speakers will do really well in there, providing from decent to great bass reproduction . Depending on the spaker choice. .
I feel a minimum and often adequate starting point for a system is 100 wpc. Unless its a SET oriented lower powered amp + high eff speakers setup. Again, smaller rooms can get away with some less power, say 50-100 I just feel better with 100wpc or better on tap for any beginning rig room size and setup notwithstanding.
Monitor speakers take up as much space as do floor standing speakers. However floorstanders usually output better low end response, though not always.
If right now you are unsure of the actual direction you want to go Id say get a receiver. If you are sure, make your best pick paying attention to the eff and impedance of the spakers you want to get and adding the proper amp to them. The room plays a part in the outcome of every rig, so that too might enter into your choices as well small room . Small speakers mid sized room mid sized speakers etc. its a debateable topic on the power levels though usually the idea that one cant have too much power carries the day while too less power is indeed a problem waiting to happen.
if 2 ch only is your pick... go with an Integrated amp. period... the issue is the budget here then. A grand for speakers and amp limits you a bit.... so I'd put the greatest portion into the INT and get just adequate speakers... figuring to upgrade the speakers asap.
Ive a 14 x 11 x 8 BR. I run a Sony ES receiver w/110wpc and a pr of 85db 8 ohm two ways up front and a pr of 87db 8 ohm 2 way speakers for rears. and a subwoofer. My office is smaller still and I use a pr of 3 way 87db, 4 ohm tower speakers driven by a 150wpc @ 8 ohm, amps, in a 9.5 x 11 x 8 and no sub is needed at all! Naturally the amps output more into 4 ohm than into 8 ohms, almost doubling up their total power output.