Can't start with a number or you won't be able to use it as a host DNS record. But yes, numbers and letters that correlate to significant information would totally be useful compared to a random string, with the caveat that putting rack/row information in a hostname would mean changing all the records relating to that host every time you moved it around in a rack. (which might be the best way to mandate that the damn NOC engineers record where they moved the goddamn host to...)