These questions are hard to answer unless one has played a large number of Nicklaus courses--which I haven't. I have played about 8 (Castle Pines GC and Castle Pines CC, Breckenridge and CC of the Rockies in the Colo mountains, Meridian GC near Denver, Ptarmigan near Ft. Collins, CO, Cabo Del Sol, Grand Haven in Palm Coast, Fla) so my sample size is limited. Of these, Castle Pines GC and Cabo del Sol are head and shoulders above the rest, and I think in their own right they are very good courses too. The routing of Castle Pines GC is very solid, with good use of the very significant elevation changes and other topography on the site. I prefer the front nine because I think there's more variety and interest. For example, holes you never see on TV are 2-6. Holes 2-4 use washes/gullies in relatively treeless areas. to good advantage. The second hole is a short par 4 with a green set angled just over a wash that requires precision and distance control. Number 3 is a 450 yard par 4 with a split fairway with a gully in the center that works (ie you really have a decision whether to go left to the wider side leaving a tougher angle to the green (also perched over a wash) or right to the narrower side with a good angle). Number 4 is a par 3 of about 200 yards to a narrow green cut over yet another wash. Number 5 is a terrific uphill 480 yard par 4 with a really wide LZ and a green cut into a hillside. The dogleg right par 4 6th requires a calculated bite off what you will driver/3 wood and a short uphill second shot.
There's good variety of driving accuracy required, ranging from bomb it holes like 5 and 17 to fairly tight holes like the par 5 8th, 12 and 13.
I'm not a fan of the early-Nicklaus style collection bunkers like you see on the par 3 16th (they are also on #5 and #6), some of the changes like the lake greenside left on 14 and the eye candy like the useless (and never touched or seen during play even by non-Tour players) bunkers in the hill on 18 are silly. But there are some really good golf holes there too (eg 9 and 10 and the front 9 holes I mention above). Of course 17 would be a par 4 in stroke play, but it's great for the Stableford IMO.