For preferences, I'm into a smooth sound top to bottom and a flat FR. I find that generally will do justice to the most genres, and would probably be the most transparent. Basically nothin taken away or added.
Re passives, I still don't quite get it, unless any passive+power amp combo at a given price would always outperform actives of the same price, then I can't see any reason not to get actives for simplicity's sake.
Genelec, Adam, Dyn are the three brands I would recommend for the above sound signature. The Genelec and Adam will be a bit more analytical than the Dyns since they are purpose built for critical listening applications. The Dyn and Genelec are the most forgiving of the 3. All excellent active monitors.
I tend to like actives for monitoring and passives for pleasure listening. The active speakers can perfectly match the power amp sections to each driver and perfectly adjust the EQ and FR to give you the most uncolored and flat FR possible. This is GREAT for mixing, tracking, and mastering but is not always the most enjoyable for casual listening. Budget conscious actives also have a huge hurdle because they have to build both the amps+speakers+crossovers all to hit a single price point. How do you choose which corners to cut when you come in $10 over your manufacturing budget? The last argument against actives for casual listening is that they are a single package. You get what you get and there are no simple upgrade paths other than selling the whole bundle and buying a new pair.
Passive speakers are much more flexible because each piece of the puzzle is built and engineered to it's own price point. It also offers many different upgrade paths to tailor or improve the sound. You can get great sounding used power amps for cheap (Soundcraftsmen, NAD, Carver, Rotel, etc) and a huge array of speaker options. Plus you get to decide which corners to cut in order to meet your overall system budget.
Here is one example of an outstanding power amp that will drive just about any speakers in your budget for less than $150:
http://www.ebay.com/itm/Soundcraftsmen-Power-Amplifier-MA5002-Vintage-Original-owner-1978-1979-model-/270948774380?pt=Vintage_Electronics_R2&hash=item3f15ce31ec
That leaves you $1300 to spend on used speakers. Here are a few options that will kill any actives in their price range (assuming you have room for full range towers):
http://app.audiogon.com/listings/focal-814v-like-new--3
http://app.audiogon.com/listings/revel-performa-f30-floorstanding-speakers
http://app.audiogon.com/listings/paradigm-reference-studio-100-v4
http://app.audiogon.com/listings/tyler-tylo-ref-system-ii-ref-system-ii--2
The Revel's and Focal's are probably the flattest response and best deal of the 4. The Tyler comes in 3rd place and Paradigm last, but they all sound great.