Question: why did create variables? It seems like unnecessary work to me.
Simon' one line would have worked. Speaking of faster workflow methods, you could actually create a Lua function to reduce the amount of characters / code / lines you need to type.function...
function char2scn(c, s)
-- + fallback + --
if c == nil then c = game.CurrentCharacter:getName() end
if s == nil then s = game.CurrentScene:getName() end
-- + set character to scene + --
Characters[c].Scene = Scenes[s]
char2scn("Tom", "Kitchen") -- set character Tom to Kitchen scene
char2scn(nil, "Kitchen") -- set active character to Kitchen scene
char2scn("Tom") -- set character Tom to currently displayed scene
... I think you get the idea.