I'm living in Bangkok, no imagination necessary.
All things being equal, I'd probably fly to Ho Chi Minh City. Only because I've never been there and I know that Phuket is expensive, crowded with foreigners(like myself and hence the expense), and overrated. Ho Chi Minh City would be a different kind of place for me.
But that's just my opinion, as someone living in Bangkok. Sorry if that didn't help you at all.