I want to replace the router/modem Comcast with a high quality for streaming

OP: I just switched from Comcast to Quantum fiber.  As a result, I have a Synology RT2600ac router and an Arris Surfboard SB6183 modem just sitting here unused.  If interested, shoot me a note with an address and I'll send them to you to see if it meets your needs.  At the time I bought them, the modem was on Comcast's approved equipment list, and it all worked fine for streaming.

@erik_squires 

"Because I do use Ethernet for much of my gear, a lightning surge from outside could take out all my entertainment devices (TVs, streamer, HT processor, DVD player.... etc.) and my gaming PC which is why I’m extra cautious."

Do you, or anyone else, know whether a fiber optic line connection (instead of Ethernet) would prevent problems in the event of a lightning strike?

@mitch2 Yes, we do know.  Fiber optic cables, lacking in any metal components, cannot transmit an electrical surge from point to point.

For this reason I use a fiber converter between the cable modem and Wifi router.  There are still potential paths through the AC wiring, but that's dealt with by a UPS with surge protection. 

The other place where Ethernet can pick up a surge is if the cabling is long.  It acts as an antenna, and the longer the cable the higher a surge voltage can build up.  Of course, whether this matters to you depends very much on where you live.  First year I moved here we had several strong lightning storms which took out multiple neighbors cable modems, and a laptop of mine (via the power cord).

Have you considered a fiber media converter set up?

I added a switch right before my DAC and put the media converter /streamer bundle from  Small Green Computer. It changed my entire listened experience.  
I’ve recently upgraded to their top tier but do have the bundle in a box.  If your Interested or have questions let me know.  It basically cleans up all the “noise” from your router and give a pin quiet signal to the DAC 

I have Comcast. I’ve always used my own equipment. Currently using

Arris SB8300 modem and Asus RT-AX88U Router