I would have to agree to, if it ain't broke don't fix it but there is a number of resources/help/advice/tutorials on tuning the my.cnf file - searching for my.cnf tuning and myslq my.cnf tuning brings up quite a lot of sites that offer information about it.
Its worth reading up about my.cnf tuning now though cause then when you do need to actually start doing it you won't have to spend massive amounts of time researching into it.
Also there is a couple of scripts out there that will give some recommendations on what can be optimized in the my.cnf, they are called:
tuning-primer & mysqltuner
I have used both of these but I would still urge you to use caution using them and you will need to ensure that mysql has been running for a few days between using the scripts, they are highly rated on some web hosting forums though.
Don't forget to ensure you make a backup copy of the original my.cnf before tuning it, also since I am a new user KH you might want to check that it is ok with them to use those scripts.
Oh and I would recommend only downloading those scripts from the official sites since you never know what anyone else could have added to them - PM me if you need the links to the official sites.
Good Luck with the tuning.