Paddle selection has many considerations these days. It use to be just the height of the paddler. These days you are right to consider the width of the boat, but you also must consider the seating height. The higher the seat, the longer the paddle needs to be. I'm not that tall and if I have a wide boat with a tall seat I need a crazy long paddle.
Check out these two links for paddle length recomendations:
https://bendingbranches.com/kayak-paddle-sizing-guide
Note: don't just look at the chart without taking the width and seat height into consideration.
http://wernerpaddles.com/fit-guide/
Good luck with your consideration.