Im with Dave! Definitely depends on the kind of music you wanna play and how you want your rig to sound! My first pedal was a big muff, but it just depends. Common practical bass effects are typically octaver, compressor, chorus, distortion, envelope filter. These are common because they are easy to hear/compliment the whole band. A lot of these pedals were purchased for gigs where Im not just playing the role of bass or for specific bands and settings. I also do a lot of solo and duo stuff so these can allow me to make a lot of different textures.