Order of loading config and constants

If I had to guess (and I do) the order is probably done that way because the defines in config/constants.php should NOT be changed. For the most part those constants correlate directly to values expected by PHP functions. Changing those values could have very bad consequences.

I use config/constants.php and config/ENVIRONMENT/constants.php to set my own application-wide and installation-specific constants respectively. I'm not concerned about the defaults in those files.

It would be nice if I could set default constants for the site in config/constants.php AND THEN set the environment-specific constants in config/ENVIRONMENT/constants.php, but the order is reversed.

So my question really is this: is there a reason for the order they are loaded? Could that order be changed in future versions of CI?