What to upgrade?


Hello,
I am interested in getting some input for a serious upgrade to my system. Currently my system creates the clarity, soundstage and dynamics a like, however this is only at lower volume levels, once I start to turn the volume up it starts to lose all the qualities I mentioned. At this stage I am not sure what to tweak and or complete change out. Listing room is currently in my loft 15 x 25, the wall behind my sitting are opens up to the rest of the house. Listing to mostly prog Rock, guitar driven jazz. My budget is 10,000 dollars for new or used equipment. My current rig is noted below with some equipment I have been researching. Thank you for your suggestions.

Portal Panache - Integrated amp
Rega p1 TT
Bellari 129 phono amp
Marantz cd5400 CDP (transport)
Wyred 4 Sound DAC
Daber Audio Monitor 3 speakers

Currently researching:

Montana speakers
Focal speakers
Totem speakers
Chapman speakers

Rogers High Fidelity amp
Pass lab
Vincent audio
Accustic Arts
Rogue Audio
musicrover
I have never heard a problem with free space behind the listening position. I agree with Mapman that you should experiment improving the sound of your current system prior to upgrading. You will likely increase the return on upgrade dollars spent.

Materials for building ones own sound panels can be purchased from ATS acoustics.
When you will buy speakers which can give a deep and wide stage you need amps which can give you a deep and wide stage. So first you need to know all the different properties of all the brands and products you are interested in. In the world of highend audio 3-dimensional sound is the most thrilling part to the absolute sound. For me it is difficult to understand why you would choose for a 2-dimensional sound? These days I only sell 3-dimensional sound. Many amps like sources of Marantz will make the image less wide and deep when you use amps and speakers which can give a wide and deep image. You cannot connect any brand to a set to keep the 3-dimensional image. It Always depends of the properties of the source you bring in. Listen also to the Platinum speakers of Monitor Audio with an amp like Pass Labs. Monitor Audio can play at extreme high volumes with a 3-diensional image to die for. They use very good crossovers for a deep and wide stage. They also have one of the best responses in timing of the units they use compared to competitors. Inside they use pure silver cable, most other brands use simple and cheaper copper wiring inside. There high. freq ribbon tweeter goes even above 100.000 hz and also makes the image even bigger. There crossovers give a lot of depth and wide. But in many recordings it also can let you hear instruments in front of the speakers. The huge image is one of the most addictive images I ever heard in my life so far! Don't buy a cd player anymore. Go for a streamer.
I have been experimenting with room treatments and have notices some improvement however not as much as I would have liked. I am seriously considering subs. Does anyone have some input? thanks.
I have sold many Rel subwoofers in the past. To be honnest I never found them or other subwoofers good enough for stereo use. I thought many times about full stealth inegration with the speakers. I never thought that this would be possible. At the end Audyssey Pro ( used my way) and the PLW-15 from Monitor Audio gave the sound I dreamed of. Sometimes even dreams can come true!
Sorry for bumping an old thread, but if you still have them, how high are the speakers relative to your listening position?  Ideally, your ears should be at or slightly above the midrange driver.