DAC Resolution vs Non-fatiguing vs Cost

I just sold my Bricasti M3 to try the much much cheaper RME ADI-2 DAC FS and Topping D90 MQA.

Both of these DACs are amazing for the money and I am now wondering how much I should really spend on a digital source.  I liked the M3 very much and the SimAudio 380D I had before it.   I was considering go up from the M3, but now I'm not so sure after listening to these two DACs in my system.

To my ears, the RME is very smooth and non-fatiguing while offering good detail retrieval; I think it is lacking a bit of bass and dynamics but a better power supply might fix that.  

I find the D90 to offer amazing levels of detail and a super quiet background, along with very good bass and dynamics.  On really good HD recordings I think it might sound better than anything else I've had in my system.  I do find it sharp and forward/fatiguing on some recordings though.  Its ultra-resolution can be a double edge sword, but man for $800 I can't believe how good it sounds.

For me, I would now like to find a DAC that has the resolution and dynamics of the D90 with the smoothness and listenability of the RME.  To get that, does it cost 5 to 10x the cost of these DACs?

I find the M3 very much a mix of these two sounds.   But I keep going back to the $800 D90 and how amazing so many recordings sound to me with it.  But yea, the many bright recordings I have do require either lower listening volumes or shorter listening sessions, which isn't ideal.

Maybe I should try a good R2R DAC next?  The D90 seems like a great reference to keep so I can compare against other DACs for resolution and detail retrieval.

I appreciate the thoughtful review.
I suggest at least trying a FPGA DAC along with a R2R or two in your quest for satisfaction. There are plenty of different units available to try on approval.
If the costliest one works best for you look for used or wait for discounts.
Just remember that some of the need ~500 hours of play to sound their best.

Happy trails
I appreciate also your impressions .... That can help much many people tempted to throw their money into the pitfall race for a dac...

Try this Nos internal battery with minimal design (low noise) Starting Point Systems dac for peanuts if you buy it used by Christophe Mariac on Ebay...

Used for 100 bucks...

I never look back....

The rightful embeddings (mechanical,electrical and acoustical) of an audio system give much S.Q. than most upgrade....
border patrol

all terrific

also by reputation (i have not tried myself)
audio mirror
Why have you not looked into the very well reviewed Schiit Yggsdrasil, with the latest proprietary unison USB chipset,or buying any used Ayre QB9.even non DSD And upgrade it for $1500 to the New  QB20 ? I would love to see how these 2 stack up against each other.
The RME ADI-2 has EQ have you tried tweaking it a bit? You'll find DACs that have  been purposely built to add distortion and others that measure so bad they just distort and some find this distortion pleasing since it resembles old vinyl and tape. I think you might discover if you use the 2 you have for a period you'll get used to what digital should be closer to reproducing the source. 
Might just be a case of finding a different unit with filter options. Both the ADI and Topping use AKM, so maybe an ESS or FPGA based offering would offer some contrast, e.g. Mytek Brooklyn or Chord Qutest. Not that the DAC chip itself is the decider, rather than other parts of the design. An observation about the M3 was that it uses AD1955s for PCM, but its own solution for DSD.  
By all accounts the M3 represents a high bar for more budget-minded DACs, and given your tastes the only one that might come close is the R2R Schiit Yggy although Ayre and Chord might also come close. I think the Sonnet Morpheus, as an R2R NOS design, might do some things a little differently that might appeal to you and might better the M3 — and that’s a big maybe — but that DAC is as pricey as the M3 so it’s not saving you any $$$, which was a major point in this whole thing in the first place. 

My only other thought would be to try a Synchro Mesh W4S Reclocker in front of the D90 to see if that might take the edge off that DAC enough to make it more comparable to the M3.  Anyhoo, hope this helps, and best of luck in your quest.  I’d certainly be interested in what you find as my tastes in sound are fairly similar to yours. 
I added a Teddy Pardo PS to my RME ADI-2 fs and it made a noticeable improvement to an already very nice DAC. Immediately I noticed a fuller sound with more weight and drive. The top in a little more calm without losing the detail but I can definitely listen to less than great recordings at a louder volume with no fatigue. Bottom end definitely digs a little deeper but is solid and fast. I will add that before the Teddy Pardo I immediately replaced the stock power cable to one I made from VH Audio with Furutech plugs and it was again noticeable better with the stock PS. I never found the bass lacking but my system and room with treatment has no problem there. Highly recommend the Teddy Pardo power supply and it’s reasonably priced. On the Teddy I use a WyWires Silver Juice II Digital series PC and it sounds great. 
I've had my RME ADI-2 DAC for a few weeks now and it is incredible for the money.    It replaced a NAD M51 which I have enjoyed for a while but never used its USB input.  Not only do I think the RME sounds better,  it does plain fact,  but the feature set is awesome. 

The NAD required full OS and drivers...  I plug my phone or Samsung Tab in and the RME recognizes it in about 2 seconds and will play anything.   Its a game changer for me.

Im 90 % music , but  Movies played through this DAC in a 2.1 set up are awesome. Subterranean bass and crystal clear dialog.   

The clarity is scary for the price.    Is it FS jitter reduction? Who knows,  who cares it sounds so sweet.

I'm keeping the M51 for my 2nd system but I was afraid it would be a lateral move and it is not.   The NAD was 7 years old it served me well.  

I'm buying a new PC this weekend so I can fully take advantage of what this DAC and my Bluesound Vault can do.

Made in Germany, nice headphone amps, huge value, sounds incredible.   The best sounding source component I've  used to date. Menu has a little learning curve but not bad at all, it is a pro component so it has a pro menu hierarchy. My money was well spent on this