Recommendations for SATA expansion?

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Long story short, mobo (mATX Gigabyte B660 DS3H DDR4) has 4 x 6 Gbps SATA connections. Old case has two bays. Purchased a new case and with my ever-expanding collection of drives, I'm retiring an old WD Green that's slow AF and have two new 14 TB drives. New case has 11 bays, I now have 8 drives. Full circle, I need four additional SATA connections.

I see PCIe cards but I know nothing about quality or architecture. I currently have a 5-bay enclosure -- which I can continue to use -- but I eventually want to make sure I have a legitimate SATA controller for these drives. I have also seen some NVMe SATA expanders, which are alluring, however my OS drive is a 1 TB Samsung 980 Pro and the other NVMe slot is labeled in the specs as "CPU" which...I don't understand. I also have zero idea whether these expansion cards are too good to be true.

Anybody have any experience with SATA expansion? Is there another route to go that I'm not thinking about? Should I just stick with the HDD enclosure for the foreseeable future? Thanks in advance!