I'd do either Beautiful Town and Night Owl or Beautiful Town and Early Bird. I tried both Night Owl and Early Bird while I was growing weeds (usually I have Beautiful Town), and I got so used to having longer hours either way. Night Owl is nice if I want to do some late-night shopping or let others on the forum do late-night shopping, but Early Bird is nice so I don't have to wait for the Cranky and Uchi villagers to get up. And I can't survive without Beautiful Town.
Night Owl and Beautiful Town. I usually play most of the time late at night but I'm to lazy to water flowers everyday... so both at the same time would be really nice.