I’m a huge fan of 29″ wheels. However, one of the cool things about 27.5+ bikes is that many will accommodate 29″ wheels without a significant change in geometry. The reason for this is that the 27.5+ tires have a taller profile than regular 27.5 tires so the actual outer diameter of the tire is pretty close to 29″. On the flip side of that coin though is the fact that the 27.5+ frame should have Boost spacing so installing standard 29″ wheels (i.e., without Boost spacing) ain’t going to work. Just more food for thought. Oh, and I agree that 2.8″ is probably a better choice than 3″ for versatility.