There are some nice cases for RPi 4 that have a semi-integrated USB-SATA adapter in the box. The DeskPi[1] case, Argon and the NESPi-style case in particular. DeskPi is pretty neat, if costly, and the NES-like cases have easy 2.5" sata swap. YMMV.
I upgraded my home LAN to 10gb/2.5gb early last year, and the RPi can't really keep up with it anymore. I'm using an N305 based mini-pc with 4 ethernet ports for my router now... exceeds my needs and runs great. My home server is an AMD 5900HX based mini-pc with also works very well (ProxMox, Docker, etc).
I upgraded my home LAN to 10gb/2.5gb early last year, and the RPi can't really keep up with it anymore. I'm using an N305 based mini-pc with 4 ethernet ports for my router now... exceeds my needs and runs great. My home server is an AMD 5900HX based mini-pc with also works very well (ProxMox, Docker, etc).