Room Layout and Acoustic Improvements on a Limited Budget

I'm interested in the opinion of those with more experience in these matters ... 

My home office, where I do all my listening, is a 10' x 14' room with a cathedral ceil that is 8' high on one 10' wall and 12' high on the other 10' wall. I currently listen at my desk on at 8' high ceiling end of the room, with the speakers on my desk, so a near-field scenario. 

There is very little acoustic damping in the room, and I can hear a mid-range reverberance to voices and abrupt noises. Since I have 3 kids in college, my means are extremely limited, so I am looking at the best bang-for-the-buck suggestions to improve the acoustics. Collective feedback and new suggestions are appreciated ...

My thoughts are:

1) Move my desk to a "long" wall so the ceiling isn't acting like a megaphone

2) Floor is hardwood, so add an area rug. Would padding underneath the rug make any difference?

3) I have large whiteboards on the walls - would it make any acoustic difference to add padding behind these?

4) The 12' tall wall is completely bare. Exposed acoustic panels are not going to fly with the wife, but I am thinking of hiding some treatment behind a hanging tapestry. A heavy tapestry would cost more than my whole audio system ($1000, all pre-owned items), so I am thinking a light façade over some 1/4" foam underlayment that I have left from taking up old laminate floor. Thoughts on that?

The rest is information on my system and myself

5) My system is a laptop computer and NAD C546BEE CD player, feeding a Chord Mojo DAC, and on to a NAD C 352 integrated amp. Speakers are an up-coming birthday present and will be either Tannoy Revolution XT mini's or Totem Dreamcatchers Cables are SKG from DAC to amp and GearIt 10AWG for speakers. I briefly considered a MiniDSP 2x4 HD to address the resonant room response, but decided its analogue to DAC process would be far below the Mojo's performance.

6) I'm an engineer, with familiarity with data processing and dynamic systems so would prefer to "engineer" my way out of the problems, rather than throw money at it :-)

7) I listen to blues, alt rock, acoustic rock and some classical. I value realism in vocals, pianos and guitars and dislike harsh, sibilant and fatiguing character. A relaxed sound is preferable over frenetic.

Thanks for reading a long question, and thanks for any responses.