Pardon my confusion since I’m new to the fediverse as well, but isn’t every Lemmy instance like the super instance you are describing? You can access any community on any instance from any other; there are commentors in this thread from beehaw.org, lemmy.world, lemmy.sdf.org, programming.dev, and many others.
It’s difficult to know what advice might be helpful for you without more context, but the one mistake I made with my last PC build was choosing a small form factor case. I thought it looked really clean not to have all that wasted space inside the case, but it makes any system changes much more arduous trying to squeeze my hands into tight spots.
Also when I needed to upgrade my gpu a few months ago and filtered to ones that would fit in the case there was literally only 1 option, it wasn’t my first choice but it was close enough I went with it instead of dealing with the hassle of buying a new case and rebuilding everything. I know for sure I will need a new case the next time I need a new gpu though.
The other thing I’ll mention is to make sure all your bios settings are configured correctly: resizable bar, XMP, etc.
Wouldn’t the home instance already have to know about the remote instance in some way for it to show up in that initial user’s search?