there are several things you can do.
actually IOS updating is most of the time quite unneseccary. what you want to update is your cios, IOS slots above 200.
you can do so by using the very first option of this guide Krank's Blackscreen Troubleshooting.
but if you didn't ran into major blackscreening problems you can stay at what you have.
if you are interested in having THE set up, i would run through mauifrog's softmod any wii guide linked below.
starting from the beginning even with hbc reinstall etc. as it includes installation of IOS58 what is used by the new hbc and some apps.
bootmii as boot2, you are lucky on that one, keep the backup in a safe place, you can also do a new backup after runningn through the guide. as a 2nd backup to fallback on.
install bootmii as ios along side if you want to access it from the hbc, for ease.
dvdx is outdated an not needed for dvd playing through wiimc for example thus it won't be installed from the new hackmii installer, you can also deinstall it.
good luck for now, hope that helps