Thank you for the feedback!
Keybinds are often a very subjective matter - but I'll try to explain why I've assigned Q to throwing :)
Q is easily reachable from WASD and some other games use it as well for actions. Especially minecraft also uses it for throwing. We also discussed using LMB for throwing, but this would not have helped any players using a trackpad.
By the way, you can have camera movement without the need to use RMB if you uncheck this in the options.