The only really young team I could think of to compare UK to was the 2003 Syracuse title team. Here's their distribution of minutes:

Carmelo - Freshman - 1274
McNamara - Freshman - 1235
Warrick Sophomore - 1146
Duany - Senior - 944
McNeil - Junior - 657
Forth - Sophomore - 618
Edelin - Freshman - 533
Pace - Sophomore - 469

No one else had over 100 minutes on the year.

Minutes broken down by class.

Freshman - 3042 (44%)
Sophomore - 2233 (32%)
Senior - 944 (14%)
Junior - 657 (10%)
Total - 6876

Here's a similar comparison for UK this year:

Teague - Freshman - 1102
Davis - Freshman - 1073
Lamb - Sophomore - 1060
Gilchrist - Freshman - 1059
Jones - Sophomore - 922
Miller - Senior - 861
Wiltjer - Freshman - 427
Vargas - Senior - 191

Freshman - 3661 (55%)
Sophomore - 1982 (30%)
Senior - 1052 (15%)
Total - 6695

So UK gives 11% more minutes to freshmen, and about the same to everyone else. The difference comes from having no juniors on the roster. They all went pro after 2010 season.

That's younger than the 2003 Cuse roster, but not that much younger.