Internet Disconnecting Absurdly Often

I have been having internet connectivity issues for quite some time now (6+ months), and I would like to finally get it sorted out once and for all.

Problem 1:

I have been awake for 3 hours and my internet has disconnected 7 times since I've been up. I am using a powerline adapter to connect to the internet, but the disconnects still happen across all devices (I notice my phone dropping connection also). Everything entertainment related in our house uses the internet, we have 2 Rokus on powerline adapters and 7 devices on Wifi (2 laptops, 2 phones, a Kindle, a 3DS, and a Switch). Because the connectivity issues have persisted for so long for the past couple of months we turn off or disconnect any devices from the internet that we are not using. There are typically a maximum of 3 things on wifi at a time (even though I know the router can handle all of it).

The Internet only disconnects for a period of 5-10 seconds, so it's not a full modem or router self-reset as those take longer. I disconnect less very early in the morning (before 8am) and very late at night (after 9pm or so).

We have a 300 mb/s plan through Spectrum (formerly Time Warner Cable), so there is plenty of bandwidth.

Modem: Motorola Surfboard SB6141

2nd Modem: Cisco 2100 Cabel Modem (Provided by Time Warner for our home secutiry system)

Router: NETGEAR Nighthawk r7000

The computer connected to the Modem/Router Directly:

Mac Mini

My computer specs:

• Motherboard: ASUS H110M-A

• CPU: Intel i5

• GPU: GTX 1070

• RAM: 16GB

My phone:

Samsung Galaxy S7

I have already tried:

Resetting and/or power cycling the router and modem so, so many times.

Upgrading the firmware on my router.

Updating all LAN and Wireless related drivers on all devices.

Yelling at Time Warner regarding connection issues. They sent someone out to look at everything and replaced some of the copper wiring, the connection didn't get any noticeably better or worse after this occured.

• When the Time Warner guy was here I couldn't get into the router at the time but he was saying something about the modem doing too much of something and then just resetting itself? I was seeing on his tablet that there were numbers consistently at 45 and then going up to 52 and then resetting back down to 20 something. I have no idea what this means, nor can I elaborate but it seemed relevant lol

Things I have not tried:

Giving up completely on the internet and just reading only books for the rest of my life, although that sounds amazing right now because your book can't be randomly interrupted for no known reason.

Modem Information/Logs: http://imgur.com/a/61mRc

Problem 2:

Ethernet over Power: http://beta.speedtest.net/result/6396571874.png

13ms, 8.08 Mbps Download, 18.46 Mbps Upload

Directly Wired: http://beta.speedtest.net/result/6396510667.png

12ms, 236.95 Mbps Download, 20.06 Mbps Upload

I recently broke the wifi card I was using on my computer, but it was around 50-60mb/s wireless when I checked a month ago or so. When I am directly wired to my router it is almost 30 times faster than when I am connected with a powerline adapter. I just used a 100 foot long cable to test the connection, I am not allowed to actually hang or drill anything to do this. Without actually stringing a cable to my router, what is the best option to get close to this speed? I have been looking into this:

https://www.netgear.com/orbi/