I've had computers with cadence and without. In fact, I currently have a Vetta RT77 on my Giant OCR 1. That computer has cadence.

HOWEVER, I just bought a new computer for my Land Shark. I went with a basic model from Supergo: clock, thermometer, odometer, trip distance, average speed, max speed, and trip time.

Cadence is interesting, but the owner of Rivendell Bicycles makes a suggestion somewhere about not keeping track of cadence. I no longer do and I enjoy my bicycling more.

Keep your bicycling as simple or as complicated as you like. For me, just being on the bike is enough.