*DAC

If you want nuance it starts with noise and jitter.

stock cables won’t cut it.  Blue jean cables won’t cut it.  There are no cheap cables that perform as well as good cables.  AV noise reduction is a must.  Then some kind of grounding box. Then you can hear what a good DAC can bring.

There is a difference between a $1000 power cord and a $500 power cord(or practically any other cord) 

Spend at least as much on cables and electrical noise as you do for the DAC.

This is what helped my system.  I'm sure you have done some of these things.  I went for low cost options that ended up paying off.

Dedicated power line or if you use lots of power.

EMI/RFI filter on incoming power

EMI/RFI on router from internet Co.

EMI/RFI on ethernet cable to streamer.

Power cords

Good interconnects.  Use contact enhancer.  Stabilant 22 is reasonable. 

Isolate speakers from floor. Spikes won't do it.

Use a good equipment rack

Isolate all components.  I used Herbie's.

You could do this and then the DAC.  Just my thoughts.  

I have Chord TT2 with Mscaler, and a pair of TeddyPardo LPS. I think the new PS Audio Direct Stream MK2 would be a great choice especially pre-loved. Chord Dave is way out of your range. Maybe a Chord Qutest, with an MScaler. I looked at your system. Lose the blue jeans cables they aren’t even close to the level of your system. You need to upgrade all your cables and add a really good power line conditioner. Depending on how deep you want to dive you could do something like all AudioQuest. Thats would be simple and a huge improvement in sound quality. You could also do all Shunyata. My system is all Audience FrontRow for signal. USB, speaker, interconnect. Then all Shunyata for Power. Upgrading all your cables and power will be a monumental improvement. 

Hmmm... Sorting through all the great comments and recommendations made for DAC’s/cables, etc., perhaps your R26 DAC choice may not need to be replaced... Yet... Tweaks such as analog/digital cabling, making sure your Ethernet signals are clean from the modem to the server if you’re using one, can enhance your music enjoyment prior to changing DAC’s. I personally have a Terminator-Plus DAC and the sound from it is superb. However just adding in an Ethernet Regenerator from Uptone-Audio took the micro-detail and dynamics up a notable level, making the streamed music sound extremely close to the music stored on the SSD drive in my music server. Also, good digital cabling makes notable positive differences in sound quality. What I’ve found along my digital journey is that it’s not always the price/type of the digital component as it is the ability to make changes that will minimize noise/jitter. Ie... Precision clocking, better digital cabling, (good grounding) minimizing noise, cleaning up the Ethernet and USB signals with Ethernet and USB regenerators, have helped me better hear changes in different digital equipment. Finally, if you have the ability to audition another local audiophile’s DAC or a local stereo shop will lend one to you to audition, this in my opinion will be better than just buying something. Synergy of components in your specific system is of real importance. Good luck in your search !

IMHO if you want pluckier guitar plucks and other sharper transients, that's probably not a DAC thing.  You can spend the thousands on the DACs that are recommended above and I doubt it will highlight transients more than your current DAC.

Unless you're talking about transient bass events (then it's a subwoofer or bass driver question), to me that is largely a speaker issue that is also heavily dependent on source material. The good news is that playing with the toe-in on your speakers can make a big difference.  But ultimately if you are not happy with the pluckiness of the guitar plucks, speakers are what you'd look at.

Also, be careful what you wish for.  When your system reinforces those plucky transients, you are also in danger of brightness and sibilance.  So you may very well get what you want at the expense of long-term listener fatigue. 

Audio is about compromises.