If you don't want to deviate too much from the style, choose types that are in tune with the rest.
An alternative, to bet on colors, choose the tone that has your style.
Bet on stylish designs, if you're a fan of design, it's a good option to bet on stylish chair designs.
Bet on straight lines, for a more minimalist decor, but still with style.
Choosing different chairs, but with the same color, will make it very cool.
another option is not to use a "table and chair set", Table of a different material and chairs.
Making a mix with chairs of different designs and materials will give that "up" in the decor. And it will make the environment cooler.