D2, D3 and NAIA all bring things to the table. The top programs are all very good. There are several programs are not that strong. A good NAIA team can beat 90% of D2's and D3's and vice versa. At all 3 levels you can find competitive programs. Trust me, the top programs at these levels would run away from many D1 programs - Here are the standards for NAIA Outdoor Track - I think one would find them similar to D2 or D3 - feel free to post them to compare:
2015 Outdoor Track & Field Standards
MEN â€A†Standard / “B†Standard WOMEN â€A†Standard / “B†Standard
100 Meters 10.65 / 10.74 11.95/ 12.20
200 Meters 21.50 / 21.65 24.80 / 25.05
400 Meters 48.00 / 48.50 57.00 / 57.36
800 Meters 1:52.50 /1:53.50 2:14.50 / 2:16.00
1,500 Meters 3:54.50 / 3:56.50 4:40.10 / 4:42.50
Mile 4:11.72 / 4:13.59 4:59.71 / 5:02.27
5,000 Meters 14:45.00 / 14:59.00 17:36.30 / 17:50.00
10,000 Meters 31:00.00 / 31:30.00 37:30.00 / 38:13.00
Marathon 2:44.00 / 2:50.00 3:34.00 / 3:36:00
Half Marathon 1:12:00 / 1:14:00 1:30:00 / 1:32.00
Due to me running low on time - I did not post race walking / relays etc.