I feel that it should have been thought through a bit more before it was opened up to speculation.
What would you have done differently if you'd been the creator behind a new currency and what would you have kept the same?
It wasn't "opened up to speculation". It simply came into existence as something with the properties of a currency, and people started to exchange it as such. Gavin Andresen is constantly counselling caution, saying there's a rocky road ahead.
I do think that adequate security is the next major hurdle to overcome for Bitcoin to make headway.
Bitcoin needs to have properly secure clients by default (and by that, I mean something that secures bitcoins as well as some of the other threads have described), and properly secure online storage.
People need confidence that bitcoins are as secure as conventional bank accounts, cash in you wallet and gold coins in a bolted down safe.