Ehh, I like dress-down church. It's more natural and sincere. I'm a flip flops guy. I wouldn't attend a church that required a dress code. God doesn't require one
For me, casual isn't as bad as immodest. There's one woman at the church I go to that regularly comes in dressed like she's ready for a night on the town ( a hooker, actually); spaghetti straps, low cut, skin tight. The teens do the camisole thing. That simply cannot be condusive to worship for a number of the men out there.
I like 'dress down' church too. Not pretentious.