Other people commented on this after longer periods of inactivity, so this should be fine as well. Especially since my remark might change the entire discussion, because a way has been found to make it work inside MineCraft Vanilla.
Via Unicode escaping, it's possible to inject any non-typable character into command blocks using JSON-formatted signs - including the § character. Some awesome guy has even made a command generator that converts formatted command text (that cannot be inserted directly) into a command that creates such a JSON-formatted sign. Workflow is simple: You prepare your command in, say, a text editor, give it to the tool, paste the generated command into the command block you want your final command to be in, activate it and click on the sign that appears on top of the command block. There's some minor issues to that tool, to be precise it can neither handle quotation marks nor produce the strict JSON required in 1.9 and later, but there might already be a followup tool where this is fixed.
Said tool is available here.