Headphone Stack (Amp + DAC + Phono) Recommendation

[aandres_gm]

Hey there. Later this year I'll be looking to buy a whole new system for personal listening, including an amp, DAC, turntable and phono stage, headphones and, down the line, perhaps a streamer as well. As you can tell, I will have two sources coming into the amp, so I definitely need it to be able to handle both. Let me summarize what I need and the products I've been looking at that, according to my research, fit the bill:

Amp:

Musts:​

• Enough power to drive anything (outside of Stax, for obvious reasons), as I still haven't made up my mind regarding the headphones
• Good measurements (well, duh, look at where I'm posting)
• At least two separate inputs, either 2xRCA or 1xRCA 1xXLR, one RCA will be taken by the turntable.
• Power button/switch on the front of the device, I don't want to stick my hand behind the device every time I want to listen to music
• Pre-amp functionality, so outputs are needed. This is to allow for a future acquisition of speakers. Future proofing, one could say.
• Good quality (build, usability, etc)

Don't care about:​

• Remote
• Screen
• Size

DAC:

Musts:​

• Good measurements
• Remote controller
• Power button/switch on the front of the device, I don't want to stick my hand behind the device every time I want to listen to music
• Either XLR or RCA output, depending on the amp
• Good quality (build, usability, etc)

Don't care about:​

• MQA
• Bluetooth

The main amp candidate is the Topping A90, as it fits all of my requirements; on the DAC side, I've been eyeing both the D30 Pro and the SMSL SU-9. Why not the D90/D70s? Mostly price and the fact they don't really offer anything the others don't. Someone suggested me to look at the RME ADI-2-DAC FS, claiming the user experience is so much more polished than on the Topping devices. Unfortunately, the RME wouldn't allow me to connect a turntable, so I had to discard it.

I'd really love to hear your suggestions. What would you do in my position? Are there any devices I'm forgetting? Thanks!

PS. headphones, turntable and phono stage are topics for another day/thread.