Some options:
https://www.amazon.com/dp/B08T6NKJDV
Obviously, you'll need an IP66 enclosure, and separate power supply, which is added expense, and added labor to your project.
There are some larger units out there, already integrated into an IP66 enclosure with power supply. . .
https://www.amazon.com/dp/B09QHYRWRZ
Definitely larger than you need, but it's a plug-and-play solution.
Caveats: I can't speak to the quality of any of these devices.
Refer to the user manual as seen here: https://motorolacable.com/documents/MG7550-UserManual-revB.pdf
(Page 42)
Log into your router, and visit the Wireless / Basic tabs for the 5Ghz band. Check your channel width settings.
If it is at 20Mhz, try bumping it up to 40, and testing your speeds again.
If it is at 40, try 80.
(This assumes that your PC is using the 5Ghz band.)
You can also try this on the 2.4Ghz band, though it's not recommended to go beyond 40Ghz on 2.4Ghz, especially if you're in an area with tons of neighboring Wifi routers.
TP-Link has the ER707-M2 router.
It has 2 x 2.5Gb ports, and 4 x 1Gb ports.
You can put your primary ISP on one of the 2.5Gb ports, the backup ISP on one of the 1Gb ports, and then use the other 2.5Gb port as an uplink to your primary network switch.
Do you have any PCs on-line 24/7 at a static IP on your LAN, such as a media server or NAS? If so, you can run AdGuard Home, to provide the adblocking you're looking for. It can act as the DNS server for your entire network.
If you cap out around 90Mb, the first suspect is the cable, since a defective cable will still allow a 10/100 connection, while Gigabit connectivity fails.
But, you had already mentioned that your link speed was showing as 1Gb.
Hopefully, that 1Gb speed wasn't manually set in the ethernet adapter settings. Can you confirm that your speed and duplex in your adapter settings are both set to "Auto" ?
I suggested it because it's a better price-point than the TP-Link that you had mentioned.
I've been using Zyxel at home (GS1900-16, GS1900-8HP, and GS1200-5) and in the office (GS1900-48HP) for a few years now, and they seem very stable. . . Haven't moved to their 2.5gb units yet.
If you're getting 150Mb on AV1000's, you might get better performance by replacing them with G.hn adapters, such as the Zyxel PLA6456. I see them on e-bay at decent (used) prices every now and then.
I do stress "might". . .
The key thing you pointed out was:
"Connected PC Directly to Modem, Finally got speeds of 1100 Mbps"
That suggests that that the source of your problem lies with the AXE7800, or the cables connecting the AXE7800 to your modem and/or PC.
Which port is your computer connected to on the AXE7800? LAN1, LAN2?
There's also the Zyxel MG-108, currently showing $119 on Amazon.
Some comments and caveats:
Post-back with the model numbers of your current Comcast device, as well as the device that you connect to for your dish internet, so we can make additional recommendations.
Most of the pro-sumer routers that support load-balancing and fail-over are wired-only routers, so if you went that route, you'd need to configure your existing WiFi router to operate as an access point.
This could get interesting if you rely on an integrated mesh system, such as Orbi, eero, Deco, or similar mesh systems.
If you only use a single WiFi router in your home, then the easiest solution I can think of would be to pick up a Synology RT6600AX router. It has WiFi, load-balancing, failover, and a bunch of other features.
If your Comcast device is a modem/router combo, now would be the time to replace it with an ordinary cable modem, since you don't want multiple routing devices in this type of setup.
I've had decent performance with Zyxel switches. I have 3 at home, and one in the office. The GS1100-24E can be found on Amazon for about $65.
Visit your network switch. Do the cables come out of the wall, and go directly into crimped-on clear plastic RJ45 (8P8C) plugs, which then plug directly into your switch? Crimped-on plugs are usually my first suspect when there is a connectivity problem.
You could certainly swap the switch-port for your room with one of the other rooms, and see if that makes any difference. However, if your crimp is bad, it could potentially start working again when the cable is flexed, leading you to believe that the switch is somehow the culprit.