Well, why is Germany underwriting their debt? It's not out of the goodness of their heart. It's because Germany didn't want a Greek default to end up giving a haircut to lenders in Euro-denominated sovereign debt. Greece isn't the only country that's "ceded the control of their currency to the EU," and fiscal unity that requires that the Greeks (and the other countries in financial distress like Spain and Italy and Portugal) give up control but doesn't ask countries like Germany and France to do the same isn't really unity, it's exploitation.
> but doesn't ask countries like Germany and France to do the same isn't really unity, it's exploitation.
Yes, if it ever happens that Germany and France need their economy bailed out in the future they should also have to give up some autonomy.
So the only options remaining for Greece, long term, are to either cede fiscal control as well, or go their own separate way again (grexit) with their own currency.
(But as I said, none of this matter as long as Germany is willing to continue underwriting their debt, which they will continue to do for years, most likely... but not forever.)