For suits, try not to wear too much black in the summer unless you add a white shirt or something to lighten up. I don't know what your budget is, but theory makes really nice easy peaces for work. You can always mix and match your suits. You don't have to wear the same suit, the same way everytime you wear it. Does that help? If you have other questions, please ask.
The dress Princessa was talking about was Valentino and they're very pricey. Like ridiculously.. Oscar de la Renta is also good, but pricey as well..