When I was young and not yet diagnosed/on medication, I experienced a great deal of depression as well as hypomania, but it was the depression that affected me the most.

Now on meds (along with lifestyle changes) that have kept me stable for long periods of time, depression really only affects me after hypo/mania episodes; afterwards I just sink into an awful depression. But nowadays, if I don't get hypo/manic, I don't get depressed, I only get down due to environmental factors.

What has always affected me most when hypomania turns into mania are psychotic symptoms: paranoia, seeing/hearing things. Very scary stuff. Increased doses of antipsychotics have generally successfully combated that, though, when it happens.