All I'd have changed about Enterprise was the tone and style (those little things). If the show had been a little wittier and more fun, more contemporary, it would have done better.
This is on the right track. But, honestly, I wouldn't make a prequel to the original Star Trek
at all. Even the new movie, which I am rather fond of, is probably too faithful to the series. If the franchise really wanted to be relevant again, it would stop reflecting the late 1960s and start reflecting 2011.