I know I'll probably catch some $hit for saying this here, but you might also want to look at a polaris scrambler 500 4x2. Most say its not a true sports quad because of the automatic and struts up front, but I can tell you it will handle your weight no problem, you'll have plenty of room, and it will run close to 70 stock. I rode mine (4x4) one night with someone on the back ( about 360-370 total lbs )and still out accelerated and had much better top end than all of the other 6 guys on utilities I was riding with. The one thing it won't do well is big jumps, but for everything you listed it will do fine and be comfortable. You'd definatly want to change the stock tires, and you could always add other performance mods. It definately won't keep up with the dale, but it would be alot more comfortable for a guy your size.

 

The DS looks big, but for your size you should really find one and try it, it doesn't feel big once you're on it. I'm 6'2" 255lbs and I love my DS. I ride with friends that have 400EX's, Raptors and Banshees and all have tried the DS and while they tried mine, I've ridden theirs. I don't want to bash any other quads, but all the others feel tiny and uncomfortable in comparison. I've never been on a Cannondale. Plus there hasn't been one person that's been on mine that has come back and said it's too big or it's too heavy. They all come back with a giant smile. You'll read that the DS isn't good for trail riding, but that's bull. 90% of my riding is on trails in New England and I have not been on one trail that has been too tight, where the 400's and the Raptors go, I go . Just my .02.