DARbarian

So the Linux journey has been long and fun, but I've gotta take a break from tinkering for a while for work. I'm down to my last few problem points and would love some assistance:

1. I want to know if there is any way at all to reduce and ideally eliminate the screen flickering that happens when rEFInd initially boots? My screen flashes gray three times before rEFInd shows up and I've tried adding & removing linux from the use_graphics_for option and mess with resolutions to no avail.
2. Is there anyway I can get an encrypted Garuda system to work with Secure Boot? I've gotten rEFInd and OpenSUSE Tumbleweed to work, but no lock with Garuda despite attempting all of the MOK enrollment and shim copying.
3. Please for the love of god tell me there's a way to Miracast / screen mirror / wireless display! I've tried gnome-network-displays and miraclecast on both distros, X11 & Wayland, native FireTV & Microsoft Display Adapter all to no avail.
4. Finally, I know this is a broken record, but if anybody anywhere has gotten a KVM program like Synergy / Barrier / Input-Leap / rkvm / nikau to work with a Linux Wayland Server and MacOS client, help a brother out.
   Any help is greatly appreciated!

Before embarking on my privacy journey, I setup a very basic IoT of all Amazon products - FireTV, several Alexa Echos, and a Ring doorbell camera. Now I am desperately trying to find an affordable replacement for them. I am planning on buying the Nvidia Shield TV to replace FireTV and open to suggestions, but I'm unsure about the others. FOSS would be great too, though I don't think I can go full hog and build my own devices.
The only FOSS, privacy-centric Echo alternative I know of is the NeonAI Mycroft Mark II, but this is $400 per unit. Since this would be a fortune just to put one in each room, I'm wondering if anything else more reasonable has emerged yet.
As for the Ring doorbell, I've seen various recommendations for Arlo, Eufy, and Ubiquiti/Unify, but I can't tell if any are actually much better than Ring in terms of privacy and security, especially for the steeper prices. Would love to know the community favorites.
Thanks in advance for the help!

I am several months into the self-hosting journey and I feel I have outgrown my Pi 4 B 8GB. I'm only running around 3 dozen containerized services and it seems to struggle to keep up. But I'm not sure of the best bang for my buck. I'd like good, long-term performance, but I don't really have a grand lying around for a Lenovo Tiny or Dell Optiplex or ASUS NUC. I'm thinking of buying an SSD to boot from, but will this even help much? For $350-500, could I make a more cost effective homeserver upgrade?

Are there any VPNs that support both IPv6 AND Port Forwarding (PF) and if so, what is the best one for privacy and security? I know Mullvad is #1 right now and supports IPv6 but not PF. So what about others like OVPN, AirVPN, Windscribe, IVPN, etc.? I have PIA right now and am eager to switch.

So two questions regarding some boot issues I've encountered on my dual-boot linux setup:

1. I want to know if there is any way at all to reduce and ideally eliminate the screen flickering that happens when rEFInd initially boots? My screen flashes gray three times before rEFInd shows up and I've tried adding & removing linux from the use_graphics_for option and mess with resolutions to no avail.
2. Is there anyway I can get an encrypted Garuda system to work with Secure Boot? I've gotten rEFInd and OpenSUSE Tumbleweed to work, but no lock with Garuda despite attempting all of the MOK enrollment and shim copying.
   Any help is greatly appreciated!