I stopped using the rack system and only use the pedals now. One reason for doing this is I am in a new band and must also drag my dual-manual Hammond XK-3c around as well. So I am keeping my melodica setup to a minimum. I am experimenting with the rack unit as a secondary/studio setup or for when I am going out to play melodica only.
I have not purchased a pedal board yet, but probably will. I want it to be small, just enough for the four pedals.
Note that the MXR M87 Bass Compressor I use will tighten up and cut the bass frequencies just a bit. I compensate for this with the Audio-Technica condenser mic; and of course, I can boost the bass all I want with the Harp Tone+ EQ pedal.