1) The Vega G2x (and now G3) are DACs with a streaming client built in. However, it is only a streaming client and can’t access network shares. The Aries can. That said, the two units also talk to one another over lightning link and share resources. The result is that the Vega G2.1+ Aries G2.1 sounds a bit better than the Vega alone. If you’re just streaming Qobuz, the Vega alone is very good. If you’re wanting the best performance, you get both.
2) From what I understand, the processing done by the Sirius is being incorporated into their new G3 platform. I’m not sure if the unit is being discontinued or not. In any case, I optimized things by incorporating the Network Acoustics Eno filter system and upgraded my network switch. Not all feel this is money well spent but I was comfortable with the result. I’m considering the Leo clock but am also looking at going upstream to the Ideon system - though that’s a really large spend from here.
The Vega did not come with a remote, but you can use a programmable remote to speak to it (including an Apple Remote IIRC.) Given what you’re hoping to do, I’d suggest a programmable remote so you can control both with it easily.
Good luck and let us know how it progresses.
Best,