@BumbleBeeBoogie,
I don't have a blanket preference. I don't think I ever wear "slacks" though. Jeans are a sort of default, they work with so many things and tend to be both comfortable and flattering (that holy and elusive duo). I'll also wear dressier pants if the occasion calls for it. When I was working, a chocolate-brown tropical wool suit (pants + jacket) from J.Crew instantly gave me authority while also not being too pretentious or intimidating. Love that suit.
But on summer days a floaty cotton dress is perfect, and for lots of other situations, depending on the dress.