I understand the feeling of wanting to replace all your hifi for a simple one-box system.
I was recommended NVA some years ago when I was looking for a passive preamp to go with my active AVI DM5 speakers. I ended up getting a P20 which worked perfectly with them. It has a CD player and Arcam bluetooth receiver connected to it.
The only 'problem' was it got me interested in NVA and I ended up getting another P20, an A20, some Cubbettes and cables etc. I then bought a P50SA.
The AVI/P20 setup is in the bedroom and the full NVA/Cubbette setup is in the living room. However, I have another pair of AVI DM5s connected to an AV amp, also in the living room. I also have a Bose Wave music system and a Bose mini portable bluetooth speaker.
I like using them all but there are times when I wish I just had one simple, high quality, portable system. I listen to the Bose mini quite a lot but obviously it's limited. I usually get this feeling when the new neighbour's kids are outside kicking a football at the windows of my flat or, when I see a new interesting bluetooth speaker!
I live in a 2 bed ground floor council flat. It used to be for over 50s and was a lovely place to live but the flats were 'declassified' some years ago so now young couples with young kids are slowly moving in who don't seem to care about other people. Sadly, not only is the site getting worse but also the area in general. This has made me think differently about what I've bought (and the money I've spent!) over the years and my priorities now. Unfortunately, as I don't own my flat (something I really regret not going for years ago) my only option is to apply for a one-bed council flat for over 50s as the council simply aren't bothered. This would mean I'd have to get rid of a lot of stuff I've collected over the years.
The thing is, if I had the opportunity to move to a nice one bed flat (or, even better, a one bed apartment in Lanzarote!) I would probably get rid of everything and start afresh and a simple, one-box speaker is something I really like the idea of.
Anyway, after all that (apologies for rambling) two portable speakers I'd like to try are B&O's Emerge and Level. Expensive but could be just right.
I really hope you find something you like.