Fx Aid is a classic: multifunction, transparent, very practical and easy to use.
Afterneath (I own the pedal version) is a wonderful effect: very deep, powerful and soft at the same time.
As for Pam's: its reputation speaks for itself...
I'm only talking here about tools that I know and like a lot. So three wonderful companions that I can recommend to you!

'On ne devrait jamais quitter Montauban' (Fernand Naudin).
https://soundcloud.com/petrus-major/tracks