+1 on skipping the suspension fork. The first thing I would suggest is deciding what kind of riding you want to do. You have bikes listed ranging from cafe cruisers to hardtail MTBs. If you are leaning toward road riding, you might want to look at touring bikes which are similar to road bikes but have a more relaxed geometry and are designed for carrying higher loads.
Take a good look at the line from Surly, they are a Godsend to Clydes with solidly built steel frames and a focus on durability rather than light weight and speed. The Long Haul Trucker is the new goto bike for heavy riders but the also have the CrossCheck which can be set up in either drop or flat bar versions, and a couple models of steel MTBs that are built tough. I don't own a Surly and have no stake in them, just passing on my observations having once been in the 300+ range myself and knowing what I wish I had back then.
If you are looking for used, I'm still a big fan of the Trek 700 series or 520s for a Clyde ride, but there are plenty of other solidly built steel framesets out there.
When you talk wheels, spoke count is only part of the picture. You can get some cheap 36-spoke machine built wheels that won't hold up as well as a quality hand built set of 32 or fewer spoke wheels. Look for good hubs designed for MTB/Cyclocross or loaded touring. My personal favorites for durability, performance, and reasonable cost are the Deore line. I currently have Deore LX on my touring bike. 36 double butted spokes hand laced in a 4X pattern will give you a good mix of comfort and strength. For rims, look for double-walled, preferably eyeletted, and wider (like a touring or cyclocross rim rather than a narrow road rim). Look for a frameset that will let you mount 32mm or wider tires and you will be set. Wider tires are beneficial for heavy riders both for comfort and for protecting the rims against the inevitable pot holes.