Cadence is a very useful feature for a new rider as it really drills in awareness of how slow you naturally pedal compared to the optimal cadences you'll notice being discussed on the forums. But it is not something you can't do without. Comes down to preferences. I would go for cadence before wireless. Computer wire spiraling down the front brake cable is a cool thing. The cadence sensor does add an extra sensor and is a little harder to integrate attractively, but it is nothing that can't be figured out in an hour or so.