Here are my picks...
DISCLAIMER:
1. As requested, these are MY FAVORITES
2. Some of these routes are hard (becasue I tend to get the most out of hard routes)
3. Some of these routes are in Oregon
4. Some of these routes are not technically part of the Cascades (but they're pretty close)
Fun Rock Trad: Zebra w/ Zion finish @ Smith -- Basically sport climbing w/ trad pro
Scary Rock Trad: Christian Brothers Traverse -- There's a rusty 1/4" bolt hanging on my wall that I pulled out (with my fingers) of one of the belays
Easy Rock Sport: Five Gallon Buckets @ Smith -- Too good to be true. As for BBQ the Pope, its good, but you guys should bring your hiking boots next time and try Screaming Yellow Zonkers
Committed Rock Sport: Monkey Space @ Smith -- Easiest free route up the monkey w/ big holds and big moves
"Big" Mountain: North Ridge, Mt Jefferson -- Jeff is (without a doubt) the most difficult Cascade summit over 10K ft. This route has everything: Crappy snow, crappy rock, crappy ice
Alpine: South Face, Mt Waddington -- Not in the Cascades, but its so cool, I think it should be an honorary member of the range
Coolest Scramble: Mt Thielsen -- what a summit!