Winterpark is the larger resort by far. 1,000 more acres. Snowfall between the two areas is similar with Winterpark just getting a bit more. Relief at Telluride is much steeper and longer. It is the San Juans after all. You can find pockets of steeps at Winterpark. Vasquez Ridge, when open is plenty steep, plus pillow lines, cliff drops, and such are back there. The problem is it's a 30 minute hike out there. The Runaway area, Awe chute, Jeff's chute and others on Mary Jane are steep too, but that stuff gets ski'd off fast. So unless you can nail it right after a storm not so hot. There are some pillow areas inbounds at Mary Jane too that are a ton of fun. Tree riding is some of the best expert trees in the state. Obviously I know the ski area. Finding a lot of the really fun stuff is tough to find though and can be frustrating. The layout is a little weird at times and you can end up walking or pushing if you don't carry your speed in spots. Kind of like everywhere I guess.
All that said, Winterpark is a complete shit show on weekends. Fairly busy during the week too, it's close to Denver. All of the area close to Denver suffer from this. Telluride is just going to not have nearly as many people. The San Juans are much more scenic too. I would definitely go to T-Ride over Winterpark. The only drawback is that there are no price breaks there. You get full pop on just about everything. This is just how it is at the "destination" resorts versus the day trip spots.