Please help fill in the blanks...

Good post, Newbee. The 2.4 is warmer than predecessors, but still on the lean and lucid side, of course, as you say.
If those hardwood floors are not fully covered, and/or you've got lots of stuffed furniture you'll have to pay attention to very careful room treatment to keep the balance from being too flat. Regardless, in-room demos of fine speakers like these are absolutely recommended. (Hint: Do you like wall-wall carpeting?)

All right. I'll slow down and take my time. I listened to the Vandersteen 2Ce and didn't care for them all that much. I can't find the 3A Signature. I'm leaning toward the Thiel CS2.4, but have only really listened to Revel RF30, B&W 703, and some Triangles. I'll see what else I can listen to, decide on speakers first, and then come back.

How's an almost wall-to-wall throw rug with padding? The room would be empty except for some heavy window treatments and my listening chair/couch. I can allow for additional acoustical improvements as well.

Thank you,

Your rug should work quite well. What you are trying to do is to reduce high frequency reflections from the floor. You should also plan to have some type of dispursive/difussion materiels on the 1st reflection points on your side walls, the wall behind your listening position and (unless you get panel speakers which is an intirely new ball game) the wall behind the speakers. Bookcases filled with books, plants, wall hangings etc work well and IMHO are not as ugly as stuff designed for audiophiles. What are the dimensions of your room - where do you think you want to have your speakers placed and listening position located? Limitations in this area could effect the speaker type/make descision. FWIW, room acoustics and speaker type are far more important than the make of your speakers and the electronic's. Put on the reading spec's and start looking into room acoustics. The end result will be more than well worth the effort. Forgive the sermon.

If you didn't like the 2Cesigs, you probably will not go for the 3Asigs. There is a definate family sound, although the 3As are much more of everything (and very satisfying IMO), and with the right upstream components are not "too laid back" as some would say. However, Vandys can sound good w/lots of different electronics, while some say that Thiels are "ruthlessly revealing".

I have owned thiel cs2.4s for six years and can verify that they are "ruthlessly revealing". I drive mine with a bat tube preamp and krell amp. Neither was cheap. If your budget is only 4-6k you might want to consider a more forgiving pair of speakers. Just giving you a heads up, they can sound awesome but plan to spend some serious money on a ss amp.