Keep in mind that where the V1 really shines is with its async USB input, and I believe the Bluesound doesn’t have a USB output.
My dealer recently recommended that a 72 would be better than the preamp in the V1, though I’ve read elsewhere that due to the nature of the fixed out of the V1 adding yet another preamp won’t change its sound that much. I guess it comes down to what you want it to do vs your current setup. Pretty sure the DAC in the V1 will be better than the DAC in the Bluesound, but for the cost of a V1 you may want to to look at other mfg dacs and stick with the 72/160 you have.
I have a 72 / hi / 140 (now and then replaced by a nap 200). I feed it with a Allo Digione + Chord Mojo. I’m a happy user of a Chord Dac. In your case, I’d try to get a Chord Dac or a sh Naim Dac - feed it by the bluesound streamer and sit back and listen for some months. Ensure the 72 / 160 are not due for a service.
Since you already have the preamp, I would forget about the Dac v1 unless you plan to hook it up to a computer.
Assuming you want to keep the 72 for its analogue input and are after a DAC:
The V1 is a line level product designed by Naim to connect to a pre amp , and has switchable earths - so no degradation is SQ when used in fixed output mode and a NAC (for example with your 72). IME, this is the case.
IME it also works well with coax and TOSLink (it has no reports of being ultra sensitive to what is feeding it upstream, unlike the Naim DAC).
A second hand V1 will cost less than a Naim DAC and brand it’s the same.
Also, unlike Chord products , there isn’t frequent ‘innovation’ or addition of missing features, as it was complete from the start (there has been one firmware update).
I chose the V1 over the Naim DAC as I preferred its presentation.
Listen before you buy of course, whichever DAC and brand. Good luck.
At some point I need a remote control dac and the v1 is on the list of potential dacs when some cash comes in ! Either that or a marantz dsc but probably the naim is better