Yup. I ask, because if you do bundle it with the DAC, you could focus funds without duplication. if you can do i2s input, that removes the need for an XMOS USB input. if you are happy with camilla DSP (and you should be) Henrik has designed a really powerful program and its free!! He is also quite responsive and its newish, so you may even be able to get features added, if he saw merit i them. that would remove the need for it to have onboard DSP processing and software and also, (and this is important IMO) it allows the exact delay induced by the particular filter you are using to be known by the host of the processing and video playback, so it would be fairly trivial to share that information with your video player, allowing it to delay video accordingly, even if you are running heavy FIR correction.
People are suggesting 8 channels, because really DAC chips mostly come in 2 or 8 channel variants. Its a pity, if it wasn't for the AKM fire, I would have a board that would be perfect for this, ready to go, based on AK4468 and opa1632. i'm aware the 1632 is EOL, but there's still plenty of stock around and anyway, there are plenty other suitable FDAs if it came to that.
Apart from more commodity chips, or ones built into Ti class D amp chips, ESS pretty much has the market cornered. crystal semi has a few, but ive never really been a fan of their parts TBH. I would suggest you may not need 8 channels for 2 way speakers ... but you would likely want to reserve the ability to add 2 subs, so 6 channels would be a minimum. For example, if you used an 8 channel chip, and possibly a lower performing one, like the 9080, or even the 'old' 9018S, you could parallel 2 channels for each midbass driver, increasing the performance for those channels in the most audible range.
As it is, i'm in the middle of designing a PCB for an 8 channel design, based on 2 x ES9038PRO, but it won't be ready for some time and, even if I end up going to market with it (its just high end DIY at this point) it won't be priced suitably for this project.