In some update that I'm not sure about, the default light key has been changed to R.
I still leave it as C.
The way server-sided keybinds work in blockland does not allow for them to be bound to a specific character key. Rather, the function that is called by a client-bound key is packaged and used as a psuedo-bind. The most logical psuedo-bind is the light key, on account of it not being a very important feature in the heat of battle and because it's close to wasd.
I think trying to use the paint button ('E' for most people) would work better than L, but I'm not sure that there's a callback that can be appropriately packaged.
There is, but, it would look odd for the client.
Their paint HUD would pop up, the tools HUD would go away, and they would no longer be able to scroll weapons. Scrolling would instead keep trying to reload.
Light key is really the only sensible key to use. Jet is already used for quite a few weapons as secondary firing modes, crouch and jump are out of the question because those can't be disabled. Brick keys would pose the same problem as paint. Freelook and toggle third person have no call back. Walk has no callback. Zoom has no callback. F8/F7 are necessary admin tools. Self Delete is necessary for getting unstuck, and would be extremely aggravating to accidentally hit because you set it to a comfortable key. Next/Prev vehicle seat are needed for TDMs that have vehicles. Chatting is out of the question. Everything under GUI is out of the question. Drop tool would pose the same problem as the Self Delete thing. Inventory up/down/left/right is mostly handled client sided, and would cause you to switch weapon. Brick selector has no callback if building is disabled, and if it's enabled, the player would have to close the brick selector every time they want to reload. Undo would pose the same problem as Self Delete. Everyone is comfortable with their brick controls and would probably not ever want to change them. Supershift has no callback, it alone only affects the client. Screenshots are irrelevant. Emotes could potentially be used, but would be just as awkward as the light situation. And that's all of the controls.
I'm pretty sure you can compromise having to use the light key, considering my entire post. You're going to have to get used to it. I'm not even sure why you need sit on the R key in the first place. You don't need it near WASD because you can't move while sitting. I have my sit button as K because there's no reason to need it near the 'action key area'.
Edit: And as for your "what about people who need their light on in dark maps?" question. In what situation would you shoot and need to reload before you turned your light on? I'm pretty sure anyone would turn on their light the moment they're in darkness. You can toggle your light on and off as normal as long as you have a full clip, or the weapon put away. There should never be a situation where you need to turn your light on halfway through reloading.
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