Include an on site search engine, table of contents or site map and good navigation bars or aids. You need a very good reason to change these basics. Compare changing them to your local traffic department having different and random colours on road signs or traffic signals. If in doubt, dump it. Bad information will undermine the credibility of your entire site.
Frames are a no no.
People cannot bookmark frames. They are difficult to exit. They get in the way. Do not use frames. Use properly organized navigation aids in place of frames.