5G home internet or 5G plus?

I don't believe the Plus plan has any faster or "higher capacity" access to the cellular network.  It's just that it offers satellite nodes to create a mesh network inside your home. If your house is big, that can be helpful as it "may" give you a stronger signal inside your home and avoid "dead zones".  It is hard to say if you need that or not.

If you had a prior mesh router in your home and felt you needed that, it may be the way to go.  Your house is "big enough" that it may benefit.  The 2.4 GHz bands will probably reach throughout your house, but it is likely the 5GHz bands will not.   I have a 5000 sq ft 2-level house and the 2.4 GHz bands can reach everywhere, including my outside security cameras.  The 5 GHz band is only available in a couple of rooms near the router.   Speeds on the 2.4 GHz band can support hi-def video (1080p x 60 fps), so it is still a pretty "fast" band, but if you have 4K TVs located far from your router, you will likely need a mesh network solution.