My old pedalboard served me well for almost 10 years. (Click here to checkout my new pedalboard.)
I could plug it to one or two amps (thanks to the Goodwood Audio Output module).
The external loop (send/return connection on the left patch-panel) was placed before the delay and reverb. It could be used for additional effects or for a preamp.
The One Control Salamandra Tail Loop offered three loops fully re-orderable. That was great for exploring different configuration, for example placing the distortion before or after the phaser or flanger.
The Digitec RV-7 Reverb was later replaced by a GFI Specular Tempus.