Yes, now that these button have disappear, i'm using key shortcut, and have Alt+Arrow-down/up will be a nice addition
Edit : Ctrl + l for load script already exist and there is some time ago i suggested shortcut for unload/new script (or if it's not me, someone else) and the result was that it wasn't a good idea, i'm not sure why but i think it's because of typo.
In fact, Omen said :
Whats wrong with the current keyboard shortcuts...
And this is imo completely Sufficient