I prefer playing normal, and feel like heavy/light body types are situational. As far as pub games are concerned, it would be useful to be able to at least change your body type from within a match in case your team needs a heavy or light type to augment it.
Same argument for weapons, though this is mostly because I just got the game and it’s inconvenient to keep quitting a server so I can go swap out weapon attachments to test them out.