Interesting way to spice up signed 3x5 cards: add sketches
 

https://img.comc.com/i/MultiSport/19...&size=original
1900-Present Authenticated Autographs - Cut Signatures/Notecards/Photographs #ALTR - Alex Trebek [BAS Certified BAS Encased]
Courtesy of COMC.com

Noticed a seller on COMC start listing a bunch of these index cards which seem to be created into sketch cards after the fact. You can see the outline of the card where the sketch was drawn around the signature. I think it really adds to the presentation. You can usually commission sketch card artists to do cards for under $100 and tell them exactly what you want to have on the card, color schemes, etc.
Definitely appeals to the new generation. I have a bunch of sketch cards, some by real comic book artists from Marvel. Others from artists who just do it on the side and then are featured in sets from Upper Deck and Topps, or are still working their way up on kickstarter or indiegogo.

Like them, or would you prefer the original index card, or the auto to be used as a cut in a custom trading card?

I'd be concerned that the sketch could possibly interfere or ruin a portion of the autograph, whether done carefully or not.