So I just bought a Hegel H390 and

Harbeth 30.1’s with a pair of RELs. Sounded great with my H590. Wilson Sabrina X’s sound even better but a bit more than your 10K budget.

Congrats on a very wise choice of amp. A friend has the 590 with Focal Kanta 2s in a room similar size of yours. I thought it would be a little bright for my tastes but it was not. 
The beauty of the Hegel is it can run sensitive or not so sensitive speakers so you have many choices. Several good ones above and
in another 12 months you might manage to hear them all.
You can go for max detail, max warmth or somewhere in between.
Open Baffle, Box or planar/electrostatic are all quite different.
Get some good XRCDs and start listening. 1st stop RMAF in Denver
in October. Love to know what you buy.

The Hegel drives 390 drives just about anything with aplomb: the world is your oyster. Try whatever tickles your fancy that suits your room(s) size and budget.

Because there is such a wide range of possibilities out there it is impossible for a third party to make the right choice for you.

+1 Kef. maybe Ref 5 or if you can, blades? 

also, using ethernet into the hegel, note that you will hear significant SQ improvements with a BonnN8 network switch (with LPS).

I understand that an etherregen (with LPS) will also make similar improvements i the Bonn8

The hegel is a great amp and it will improve further with noise reduction from ethernet and also from power supply/power conditioners. 

Hello,
I agree that the Hegel gear sounds great with a lot of speakers. My recommendation is KEF Reference 1 bookshelf on the matching stands for $10k. Don’t be fooled by the bookshelf description. You do not need subs with this. When you go to shows KEFs are being driven by Hegel gear a lot. If you need towers go with the R line which is less expensive like the KEF R5 or  KEF R11. This store sells both in the Chicagoland area:
https://holmaudio.com/
If anyone has either of these brands and wants to demo them to hear for themselves you should stop by this store.  They let you demo products in your home. When I was in the store pickin up my Hegel V10 phono stage that I ordered they had the H590 hooked up to the KEF Blades. The other big room is where they had the Hegel H390 and the KEF Reference 1s on sound anchor stands. They look good with both stands. I prefer the KEF stands. Another option is Maggie’s with the JL Audio Subs. This would be $10k also if you bought big enough Maggie’s and the F series JL Audio subs like a pair of JL Audio F110 subs. 
This store is not a Maggie dealer. Maggie’s also sound great with REL subs. I own both brands and love them both. I hope this helped you out.