I have thought about this many times while sitting in the water on low wind days drifting towards somewhere I don't want to be and waiting for a good enough gust to relaunch my kite. I think the much better plan is to have a powered board so that you can generate apparent wind in the lulls and/or tension the lines enough to get the kite back up in the air when it is down and there is not quite enough power to relaunch.
Granted some of these exist with motorizing the board, but these are challenges that I think you will face with kitesurfing combined with electric motors in the traction kite:
Do not underestimate how powerfully electronics and saltware don't like to mix. I have ruined RC boats with only a few minutes of use in the waves before... but damn was it a fun few minutes!
2. Every extra protrusion on the kite is 10 more ways to cause a kitemare.
Especially because this type of adaptation would only be useful in low wind days you are going to have higher odds of wrapped lines from oddball crashes with lulls and gusts where the kite might hindenburg or bowtie
3. Extra mass on the kite sucks.
It is going to make the crashes harder, it will create new stress points where they could tear, or even pop your leading edge on hard crash. Most of this mass is going to be the battery. You just couldn't pay me any amount of money to put a battery on one of my kites. They can come down really, really hard I would think you are destined for a fire and or killing someone with an unlucky, direct hit.
These f-ing, blue haired, condo dwelling a-holes that hate seeing anyone have more fun than them are already doing everything in their power to limit our access and legislate against this sport. They are using every excuse in the book from public safety, to 'it scares endangered nesting birds' and all in between. Add motors to kites just gives them one more thing to fear and start calling it a motorized vehicle or airplane, etc. I think technically by adding a motor you would officially be reclassifying your kite either FAR 103 and at the very least believe it or not it would also fall under drone laws as well and need to be registered. Yes, anything over 250grams with a motor that goes in the air must be a registered... and yes, even if it is tethered to the ground.
There are several other reasons in my head, but these should be enough to help convince you to try doing it with a motorized board first. If you decide to go ahead with this please take some video, because I would love to watch the carnage and/or help you tear up $800-$1200 kites by the dozen.
Any grease is better than no grease.
The best exercises are the ones you enjoy doing.
I strongly prefer vehicles without doors.