A Plus is neat for being able to run down to .97 (or .85, they say), but beyond that, they're kind of short on usefulness.

A SE with dual 1.44MB floppy drives, max RAM, an accelerator and a hard drive shoehorned in is a massively better computer.

A SE/30 is better still, but you won't get dual FDDs.

A IIsi almost entered into my possession. Neat machine.

A USB external floppy drive will never be able to read 800K or 400K MFS disks. Not even the Imitation SUPERDISK drive can read them, as described here.

Networking is described in detail concerning LocalTalk (usually PhoneNET) and Ethernet, as well.