‘(...) I'm going to extend my rack to another 3U of space’.
Honestly, investing directly in another RackBrute 6U would be wiser... Then a few suggestions:
Dirty textures: NE Viol Ruina ?
Melodic: Stochastic Inspiration Generator ?
Noisy: EI Liquid Glitcher ?
Enjoy your trip! :)
'On ne devrait jamais quitter Montauban' (Fernand Naudin).