Golden Heroes-style random character creation gets you to a character, but not necessarily a balanced one. Part of the challenge for players is rolling with what the dice give you. Granted, not all player groups are up for that.
It's worth asking, what supers systems generate balanced characters? I'm not even clear if Champions is perfectly balanced, despite decades of play and revision. I remember both Superworld and GURPS Supers generating some quite unpleasantly lethal and un-comics-like combats.
In my experience, Champions is the most fair balance of any of them I've played - because the rules conceit is you buy the effect, and describe freely how it happens. But that balance is only in-campaign, since there's so much subjectivity in the character advantages and disadvantages, and in some of the power modifiers.
Sentinel Comics is next - it has a balance system, and growth is so carefully handled that it remains relevant for a good long time, but it can (and does) get really swingy in play. There's some chances for players to accidentally nerf themselves, but I've only had one player fall into that. He got a rewrite after one session. Again, it's buy the effect, slap a description on it...
the palladium options don't even try to balance (Heroes Unlimited, Villains Unlimited, TMNT, After the Bomb).
GURPS fails to balance because GURPS was originally buy the cause... and the three superhuman abilities types in the system (Magic, Supers, Psionics) are each internally moderately balanced, but a 500pt wizard is going to kill most 500 point supers...
TSR's Marvel games made no efforts at balance. It was, however possible to use the rank numbers to get a relatively valid balance - per character, I averaged FASE, and added the average of the best three offenses and best defense or movement power. Was kind of rough, but kept me from instaganking the party. For casters, I swapped Psyche for Fighting.