"Sonic preferences: I value transparency and imaging/soundstage. Bass should be accurate above all, as opposed to chest-pounding powerful".
Rebbi, you'll note your above statement. THAT is the reason I suggested the Triangles. YOU described the sound YOU wanted.
That is Triangle to the letter.
There are hundreds of great speakers available. I mean really great speakers. However, try to keep in mind REQUIREMENTS vs. preferences....
You NEED close to wall. You NEED efficiency. You NEED room dampening. If you don't use the above as minimum requirements, it won't make a bit of difference what the nametag says. Ultimately the sound will be less than desirable. Room acoustics could make a pocket radio sound fulfilling.
Also, and with all due respect, I disagree with a "pretty extended" or "sizzly" or "bright" definition being used in conjunction with the Triangle line. If the high frequency is being considered (in my terms) "overly significant", it is more than likely the speaker simply exposing a problem upstream IE: Bad AC, Impedance mismatches, Vibration issues, etc.
In general terms..... A speaker that is "extended" in any area of the frequency range, will have difficulty projecting imaging in a proper, balanced perspective. Triangle imaging is virtually holographic. With a 91db efficiency in that sized room, your amplification will feel like it's vacation.
Last but not least.... Room acoustics. Otherwise..... Don't blame the equipment. :>)