Adroitfixed, we are about the same height and weight. You can go 28H but I would not recommend it unless you are TT or racing. They will be faster and lighter, but they will also come out of true much quicker and will not last as long (brake spokes). Light fast wheels are great but the trade off is durability.

If you are racing then you really need at least two sets of wheels. A fast set for racing, and another for training. If you are just cruising around, I would stick with a 32H rear and either a 28 or 32H front.

What kind of set up do you have now on your rear wheel (hub, spokes and rim)?