I suggest that the Command block interface get's expanded and the input and output bars for the commands get expanded. I saw a mod made by CrushedPixel on YouTube for 1.8 and i thought that it's just a minor change that will help any map maker, like myself.
I updated the post with the link. As you can see the input window for the command is bigger. I'm not suggesting for the coloring of the parts of the command but i do think that the bigger interface should be implemented.