I played the Cascades (Upper) this Spring and cannot recommend it highly enough. It has such great features: cool greensites, uneven lies, a number of downhill tee shots where the hole is literally right there in front of you and some quirk. The only negative are the two rather plain Trent Jones holes on the back nine (a par three and a par four (14 and 15 I believe). I would play it as much as you can.
The Old Course is fun and a nice way to ease yourself into golf at the resort.
The Lower Cascades was not open when I was there in late April. Can't opine on it.