I've had K Elites on my Gunnar cross bike for 3 seasons. No cross racing, but plenty of time off road, commuting, etc. No problems.

Ultegra or Chorus hubs, depending on your component group. 36 spokes. Open Pro's are very nice. If you want something stronger, go for a CXP33 rim (make sure the builder uses 14mm nipples- needed for the deeper section rim). Go for all brass nipples. Rebuild the hubs with some nice grease, like Phil Wood. I'd probably build them up with spoke washers too, just to be safe. At your weight and purpose, don't mess around with low spoke wheels. I also much prefer cup and cone hubs to those with cartridge bearings, at least for your everyday wheels. They're much easier to service and you can find them anywhere. The Ultegra hub is my all time fav. They just work.

I concur with Greg K, at 90kg 36 holes would be nice. I wouldn't mess around with trick wheels unless you were trying to win states or podium at nationals or regionals. Cross is pretty hard on equipment. With all that said I have seen some Mavic SL take some pretty good abuse and live to fight another day.

Now you really get to have a good arguement of clinchers vs tubies and Tufo makes probably the best line of tires. Excluding Dugast. Let the games begin.......

I like either the clincher tubies or pure tubies as you can run super low pressures if the course calls for it.

I'm riding a pair of CXP33 rims on Ultegra hubs on my cross bike. You can pound 'em pretty hard and not damage them. I have thought about putting my Ksryiums on, but why mess with breaking an expensive and hard to find spoke?