Changing Mullvad server at router level

Reddit is becoming increasingly more and more hostile to VPN connections to the point where I often get the "whoa pardner" error message and have to try 4-5 different VPN servers on my desktop or phone before I finally get one to work with Reddit. Same thing sometimes with Google/YT, it keeps asking me to prove I am not a bot and a bit of experimentation with the servers gets me through.

This makes me wonder, is it as easy to switch my Mullvad server on OPNsense? I get the sense from the YT videos I have watched, I have to effectively setup an entry for every Mullvad router as separate instance on my OPNsense' VPN WireGuard settings and toggle which instance is being used at the router level?
I know I can technically have Mullvad on my router to hide all my traffic and then on all my devices that I use Reddit on, I can additionally have Mullvad on them too and play with the servers I am connected to on my device specifically until I find one that works but I am curious what the workflow is if I choose to do all my Mullvad related configs at the router level.

Making custom block?

I have a love-hate relationship with Reddit. On one hand, I can't deny that certain subreddits are useful as someone in tech, but I also can't deny that certain subs are just a time-sink and some subs are just toxic (looking at you AITA). I can often prevent myself from browsing the time-sink/toxic ones but sometimes I lose myself in them and I am in search of a way to block them via Mullvad at my router. Obviously a DNS-block won't work if I want to block reddit.com (the home page) and certain specific subreddits but leave any other tech related subreddits open for me to read so the next best thing I assume is some kind of firewall? But I don't know if such a firewall exists that can basically start doing regex on a URL to see if it should be accessible from within the network? Which makes me wonder if I can create my own firewall but I don't even know the first step, as in would this be something that integrates with OPNsense, or a stand-alone program I have to create myself? I know Python, Java and have some basic knowledge of C++ but don't even know if those are the language I need to know to create such a filter or if the filter I am looking for is even possible? Any and all pointers welcome.

I currently have a Netgear R6700 - Nighthawk AC1750 router that has reached end of service and am looking for a replacement.

When I set up the router, I had issues with some of my devices not connecting to either WiFi 6 or the 5 GHz band (I can’t remember which was the issue) so I had to set up a guest network for those devices to live on.

I would like, if possible, to have one network that everything in my house can connect to, but that’s a preference not a necessity. Are modern routers fully backwards compatible with older devices?

I’d also like something with a relatively long life ahead of it (though security is paramount and I’d rather have a secure router that I have to replace sooner over an insecure one that lives longer).

My house is just over 1000 square feet so coverage area doesn’t need to be huge. I do stream a lot of games to my laptop via Moonlight though, so being able to continue to do that without lag/hiccups is a necessity for me.

Let me know your recommendations and avoids, as well as any advice you have.

I've not bought a new router since 2010 because I try to physically wire everything in my house so it's pretty much my phone using Wifi.
However, I've found great use for my Steam Deck as a streaming platform on my TV using Moonlight and I'd like to get a new, good router to support it.
I think the Steam Deck can support Wifi 6, but I'd like a Wifi 7 router if possible so I can future proof the possibility of getting a new wireless VR headset too. Though I'm not 100% sold to the idea if there's good argument to just buy Wifi 6 today.

Long story short, I'm finding it really hard to choose what router to buy. There's so much "gamer" junk.
Reviews are all over the place too, site A will give a router a top recommend and site B will list off a huge range of cons.

Does anyone have any advice? I just want a good, reliable, high throughput router and I can't be bothered with the returns process to try and buy if possible.

I'm running out of time to finish the spend requirements on a credit card promotion. I was planning on buying a VR headset, but I realized there was something that would actually be much more useful; a new router.

The market for consumer routers has been really strange; We are on the sixth generation, yet it's super common for consumer routers to be two or three generations behind, especially the less expensive ones. So much of the stuff on the market only goes up to 802.11n, and half of the time the firmware they include is halfway broken or is missing important features.

So I'm looking for a router that is relatively future-proof. I want Wifi 6. I want something that won't be interrupted by the microwave. Open source firmware would be excellent, but not a requirement. I don't need mesh networking; my house is not that big. I do want it to be relatively inexpensive; I'd consider $300 to be a hard limit unless someone has a persuasive arguement to justify the cost.

I would also prefer to avoid Netgear. I have no idea how they stay in business with the mountains of problems I have had with their products and their horrible support. The last time I owned a Netgear product, I was forced to give them my email address to download the driver and they illegally added it to their marketing mailing list without my permission. I don't do business with people who betray me.