Confirming a few things in my audio setup

[profoundnoah]

Hey Guys,
So I am fortunate enough to be receiving a complete audio tech upgrade for my Birthday, coming very soon. I've already gotten a list completed, and it is as follows.

HD 600's
https/www.amazon.com/Sennheiser-Open-Back-Professional-Headphone/dp/B00004SY4H/ref=sr_1_1?ie=UTF8&qid=1495403032&sr=8-1&keywords=hd+600

Mackie CR4BT's
https/www.amazon.com/Mackie-CR4-Pair-Reference-Multimedia/dp/B015U623GW/ref=sr_1_1?ie=UTF8&qid=1495535424&sr=8-1&keywords=mackie%2Bcr4&th=1

Schiit Magni 2 (Amp)
https/www.amazon.com/Schiit-SCH-0702-Magni-Headphone-Amplifier/dp/B00SCBKPW2/ref=sr_1_1?ie=UTF8&qid=1495409447&sr=8-1&keywords=schiit+magni

Fiio D3 (DAC)
https/www.amazon.com/Digital-Analog-Converter-Optical-Toslink/dp/B005K2TXMO/ref=sr_1_5?ie=UTF8&qid=1495409592&sr=8-5&keywords=DAC

I'd be using this setup to help me in future audio production and also to upgrade my listening/comfort experience, as I'm currently running V-Moda Crossfade M-80s along with a blue yeti mic.

So here are my questions:
1. I prefer to have all cables routed in the back, considering it is much more aesthetically pleasing. The Mackie's run via RCA cables, so I should be able to use the included stereo to RCA cable to get sound, correct?
2. For my Amp, which requires an RCA input, I can just hook it via optical (through the fiio D3) and have no problem with having to always plug/unplug one source, it should be able to be changed via playback devices, or?
3. Is the schiit modi 2 uber worth it? It's quite a large premium for a DAC, but features the two RCA outs I would need in one package, and I've heard raves about its quality. Would it be a worthy investment?

 

[americanaudiophile]

The DAC is critical to the sound quality so don't skimp on that. The Schiit is excellent bang for the buck. The DAC in the Fiio may not be any better than the one PC mobo already has. A soundcard might be better than the Fiio but not likely better than the Schiit.
I would hook it up like this
DAC to PC via usb. You might get better sound if you used a USB cable that doesn't carry 5v from the PC.
Split the RCA output of the DAC with1 male to 2 female RCA Y splitter.
Connect the headphone amp and speakers to the splitters.