Good Speakers for Low Watts

I used to have a Musical Fidelity A-1. It gets very hot, enought to fry an egg on top. Be advised most units have volume control or selector switch failure due to the knobs breaking. My selector switch broke. I finally gave the amp away. I'd have to say it was a really nice unit for the money, purchased for something like $350 back in 1985. What about the Class A Belini amps?
Speakers: Believe it or not I used a pair of Spica TC-50's and it was loud enough for me. If you have the room, a pair of Altec 19's or JBL Jubals or L-300's if you want LOUD with 20 watts...

NHT SB-2 or SB-3. I used a pair of the 3s with a 50 watt Audio Refinement Complete. Very smooth sound and good at low volume.

I own and like my klipsch Heresys . However as a bass player you will find that they roll of entirely at 50cps and start their decent at around 100cps. In additiion you would be smart to buy the Original Heresy not the ll or lll.
The price for a pair of the ls is closer $400-$500 in good to excellent condition. There are ways to improve the sound by changing to a new crossover, which is a good idea anyway. That adds considerably to the cost.
Low level listening to low frequences is why vintage equipment had a "compensator" or the later "Loudness" switches. I have read that at low volume the low frequencies get lost thus the bass boost. These are things you might consider.
I can say that most small monitors in the price range you are talking about are very good . However they are generally incapeable of producing really low bass. To the average ear, it is barely noticed.