How much to spend to improve Linn Klimax

I have one of the first generation Linn Klimax Renew. The audio board is the later revision with Dynamik power supply.

I have no compliant, but what to get a sense what is the next step in sound quality? I know I can always step up to the latest Linn Klimax, but the cost is prohibitive.

The rest of the gear is Harbeth M30 and Ayre AX-7e
I am going to copy and paste my Bricasti impression here from over 3 years go. I know alot have changed for Bricasti, including several firmware updates to add more filter options and other power-related enhancement. Given the foregoing, my impression should be taken with a pinch of salt.
I had a chance to audition the highly-praised Bricasti M1 at my dealer. The associated gear include ATC 100 passive floor stander, ML pre and mono block. We used playback designs MPS5 for comparison and as the transport. I auditied this DAC hoping to use it as a secondary source to my Klimax.

We used primarily Diana Krell's CDs, including Live in Paris, and violin solo and concertos.

The positive:

M1 is technically excellent. The highs are extended without harshness. Mids are fairly transparent. Bass hits deep with power and definition. M1 reminds me of DAC1 and dare I say it's a souped up DAC1 in every respect (could be a good or bad thing)

The negative:

I would say the biggest weakness and ultimately my dismissal of this otherwise technically proficient DAC is its ulter lack of musicality. For example, human voice do not sound real and organic when compared with MPS-5. When Diana sings, I did not get the imagery of her singing. Like the mids, the highs on M1 leave much to be desired. For example, symbols in Living in Paris and violin solos lack the real life quality associated with those instrument. M1 sounded just like another digital DAC, displaying all the negative aspect of digital music. On the very high notes of violin, all I heard was a monotone sound, without the usual harmonics and woodiness I am used to with Klimax and what I heard on MPS-5. Soundstage of M1 feels contrived and not realistic. I did not hear the complex layering as with he MPS-5, nor did I hear as deep of a soundstage.

I believe if you like how DAC-1 sounds and wants a more refined and upgraded version of that sound, M1 may be a great choice. However, if you value real-life organic sound with music unfolding in a natural way, you may want to look elsewhere.

Overall I was very disappointed in the M1 when I had very high expectations after reading the latest review in an audio magazine.

"07-19-15: Chesebert
Kimax Renew was in the same price range as Bricasti, so I'm not sure where the over priced / over rated comments came from. "

I don't know why you would expect me to compare the Linn with some other random dac just because its close in price. Probably because it got good reviews. I don't waste mt time reading them.
If you have the first generation of Klimax Renew - DS/0 - and if you don't want to spend more than $15K, then the only way to improve the SQ of you system is the second generation of Klimax Renew - DS/1. There are plenty of them on the secondhand market. The price is between $5-6K. For the price new Renew DS/1 is a great bargain! No DAC+digital transport system under $15K can compete with this device.