SATA power delivery limitations on Sigma?

I want to use the Sigma (in part) as a media server, one that I can use to intake media from an optical disc as well as playback/stream stored content. I'm going to have all my spinning drives for backup and archive in an attached USB enclosure with its own power supply and cooling, but I'm planning to attach a Blu Ray optical drive and some 2.5" SATA SSD's for my media server. 

I found an M.2 PCIe 3.0 x4 adapter board that will add six more SATA ports, and IcyDock has a 5.25" bay enclosure that will accommodate a slim optical drive and six 2.5" SATA drives (ToughArmor MB606SPO-B). That enclosure gives one pair of SATA data and power connectors for the optical drive, and I'm going to connect those directly to the corresponding headers on the motherboard. The drive cage provides 6x SATA data connectors, and those will be plugged into the M.2 adapter board, but those 6 SATA drives are sharing a single SATA power delivery connector. See my ugly sketch below:

To my knowledge, the specs for SATA power focus more on connectors, pinout, and voltages- which means that your mileage may vary using daisy-chain cables to power multiple drives from a single header. Is there any data that LattePanda's support or anyone else can share regarding the Sigma's power delivery limitations? 

I could use a daisy chained connector to power the optical drive and all 6 SSDs from that single header on the motherboard, but I'm concerned that the Sigma may find this to be abusive (especially if I have drives in a RAID 0 where they're all reading and writing together). Would I be better advised to find an alternate means of power delivery for the 6 SSDs in the SATA cage?

*note: My plan also means that the heat spreader plate on the bottom would need to be removed to make room for those SATA connectors, so there are thermal implications here that need to be addressed separately. But I figured the power delivery question was legitimate enough that it's probably worth asking.