Hardware Upgrade Suggestions (again)

I am currently running the following set up:
Mac Mini (late 2012) 2.5ghz I5. 16gb Ram
2 x External Samsung SSD’s - 1 carries OS + Roon, 1 Hi Res Audio Files

Connected via an Ipurifier2 and Tellurium Q USB cable into
McIntosh 5200, plays out to Sonus Faber Venere 3.0.
I also have a Oppo UDP-203 connected via my home network.

I am generally happy with sound quality - tend to use Roon for it’s bullet proof convenience and Audirvana because it give me a little greater clarity but less warmth (please lets not turn this into a Audirvana vs Roon discussion and ‘am I actually measuring clarity’. I’m not. It just sounds that way to me…:0))

The McIntosh can sound a little flabby; Audirvana tightens bass a little however can be a little shrill for my ears and lacks the stability of Roon. The Oppo outputs a well balanced sound however it’s a bit anodyne - I feel that theres more to be had.
So, given the current set up, I’ve been considering the following:
Moving away from the Mac Mini and installing something that holds all my files and connects to the McIntosh.
Continue to use the Mac Mini, add in a better external DAC and continue to play out to the McIntosh. (The 5200 is only 15 months old so it’s staying, no mater what!)

I guess what I’m after is something better than I’ve got. Greater clarity, separation, sound stage, punchy bass etc.

I’d be interested in the opinion of people who may have trod this path previously, or perhaps have installed pieces of equipment into their system and been blown away by results. And also, am I searching for something that isn’t there? Am I unlikely to make any significant improvements unless I spend a bucket load of cash - which I’m probably not going to do. Lets say ITRO $2k for budget… I’d welcome your input. Cheers.