I had the 300Hz roofing filter and I did not have either the NB or the NR engaged Brian, I have owned enough Yeasu radio's to know well the NB engaged is like opening up the IF stage on a superhet. Since were on that point the NR in the 7300 is much better in reducing band noise which makes it more comfortable to listen too for hours on end plus does not have the under water effect unless turned all the way up. Maybe the MU tuned options on the Yaesu would have improved things somewhat but by the time you end up with all three filters plus it leaves out 10&15 meters your at a way different price point. Hell I liked my 3000 but that little test during the CQWW CW weekend showed me that the 7300 was a clear game changer but also buy reading lab reports I also found that the 7300 had more sensitivity than most other rigs so that was the only thing that had to be tamed. Many of the Youtube reports showing the 7300 getting overloaded were with radio's were the op would have the Pre Amp stage engaged, clear and simple these folks never did RTFM.
I also think Icom may be missing the boat here as well, at some time the sales of 7300 rigs are going to drop off, yes they have that DC to light QRP thing which is an overpriced Tonka Toy just like the Elecraft KX3 is but to me that is a nitch market. Then they have the 7610 which is $2k more than the 7300, they really need to look at maybe a 7300 or SDR version of the 746Pro, yes HF 6&2 same package, separate antenna jacks plus RX in/out, I/O output so you can use it with HDSDR software for a great pan display and a slightly larger color screen display at around the $2K selling mark. There IC9100 did not last long, nobody really cared for the above UHF and microwave bands but HF six plus two gives allot of station in one box and clearly every 746Pro I hear on the higher bands sound 10 times better and no were near as wide of an SSB signal as those dirty little Kenwood 2000's, every one of those Kenwood's I hear on six is 10 plus Khz wide!
The way you have your 3K with the external MU tune units may improve close in operation but when I lived up north on Long Island NY for most of my life having some of the biggest super stations either around me or there close proximity during a contest weekend on the low bands the 3K didn't cut the mustard so maybe the MU tunes would have helped but the bare bones 7300 really shocked me, I thought that radio would turn to dust but it held its own against the 3K. BTW I stopped reading all the add copy a while back, Yeasu does a great job on there brochures but the proof is in the pudding!