Your idea is good. I've posted it as a suggested improvement in the Ideas forum.
I don't know of a way to search on the hotness level of a card you don't own. If you own a card, the .xml file in it's data folder has a numeric hotness level code that indicated the highest hotness level for that card. As an alternative, you can examine the third digit from the right of each clip number to see the hotness level of that clip. Doing this can give you a count of the number of clips in a card at each hotness level. I wrote a script to do this on my Mac and load the results into an Excel spreadsheet. Here is a very small sample of the results.
Model Card # Card Name No Nudity topless nude Full Nudity X rated
Olga Barz a0656 Quick service 13 7 2 2 5
Olga Barz a0657 Apple juice 13 6 5 4 1
Olga Barz a0658 Tenderness break 7 6 5 3 2
Olga Barz a0659 Smart style 13 5 4 5 1
Dominno a0678 Basketballs 14 7 1 2 2
Dominno a0680 Punta Cana 15 8 1 4 3
Dominno a0681 Cherry brandy 11 8 0 6 2
Melisa a0690 Sweet Candy 15 5 3 2 2
Melisa a0691 Happy sunday 10 10 1 3 2
Abigaile Johnson a0722 Words of love 11 5 0 5 3
Abigaile Johnson a0723 Divine delight 11 7 0 4 5
Abigaile Johnson a0724 Afternoon snack 11 10 0 5 2
Abigaile Johnson a0725 Deserted island 12 6 0 6 3
Ashley Bulgari a0734 Jungle Pub 12 9 1 4 2
Ashley Bulgari a0735 Magic moment 10 9 1 3 3
Ashley Bulgari a0736 Wonder Island 14 11 0 1 4
Ashley Bulgari a0737 Pure Sex 14 6 1 3 3
Ashley Bulgari a0738 VIP Party 13 7 2 2 1
Natalia a0739 Warm kiss 14 7 0 8 1
Natalia a0741 Black phoenix 12 7 0 7 1
Danielle Trixie a0746 Hot zone 13 6 1 6 3
Jana Cova a0751 After work 11 8 0 3 3
Jana Cova a0752 Castle life 9 6 0 6 4
Jana Cova a0753 Red sun 11 7 0 1 4
Silvie Deluxe a0754 Deluxe version 11 9 1 2 3