Are NHT VT2.4's harsh, or is it just me?

The NHT's can be harsh with the wrong equipment. Let them break in a little bit and see what happens. They're actually a fairly revealing speaker although I have personally liked the 2.5(not the 2.5i) for home theater. They have the soft dome and I find it more to my liking. Good luck.

If you want to "push" the woofer break-in, aim the speakers toward each other, wire one out of phase, turn the bass up, and let 'em pound away for a few hundred hours.
THEN listen. The tweeter will still be bright because that's what NHT's always been about, but at least you'll then be able to give them a fair hearing....
I wouldn't be surprised if you still found them a bit wanting...due to a "U"-shaped spectral response...the old west coast sound. You can modify the bass end with room placement, but the midrange will probably still be pretty sucked-out vis-s-vis the treble. Do these come with a tweeter pot or switch?

I used to listen to my 2.9's with socks between the tweeter and grill, if that tells you anything.

After a full evening of listening, they do sound better. The bass has become much tighter and more full.

The tweeters are very revealing of the source material. They sound excellent with some CD's and metallic or "tinny" with others. I compared them with my old Genesis speakers and I generally prefer the NHT's for their dynamics and that "you are there" feeling. Amplified highs don't necessarily sound perfect when you are at a live performance (with blaring horn tweeters) either. It seems that the more I listen to them, the smoother they get (or else I am going deaf from listening too loud and can't hear the high notes anymore). I hope the trend continues.

If there are any shortcomings on music, they certainly don't exist in the home theater realm. I put in the Pearl Harbor DVD and WOW! I've never heard the air raid like that before. (Using NHT VS2.4 center channel, NHT Super One in wall surrounds and M&K push/pull 12" powered sub).