I'm sorry this answer comes so late, but hope the information helps anyway!
The theater during Renaissance times was very dry, stiff, and formal. The actors and actresses often spoke in rhyme and used eloquent speech. At the same time, there was ample opportunity for expression with their faces and bodies. Things were mostly tragic, with little time for mirth. But, when they did laugh, it was mostly at themselves and their way of life. Shakespeare, especially, used a lot of satire, poking fun at many of the social practices and customs of the day.
The costumes of Renaissance times were very elaborate, colorful, and detailed. I think the costume was as much a part of the character as the dialog he used! If someone was a court jester, for instance, the costume itself pronounced him as one without his ever uttering a word. It left no room for the imagination, and characters were expected to stay within certain parameters and behave in expected ways.
Nowadays, the theater is much less formal. A costume is no longer a stereotype of the character. Actors and actresses have free expression of speech. But, to say modern theater isn't anything like the theater of Shakespeare's day would be an incorrect statement. Why else would we strive continually to measure up to the theatrical performances of yesteryear?
Renaissance theater laid the foundations for modern theater. And, it continues to mold and shape it.