Do you/have you created Kira art now or in the past?
Yes - in the past

Any anecdotes about your experiences as a Light Yagami artist?
I developed a strong appetite for potato chips, preferably Sour Cream and Onions.

How would you go about creating a Kira drawing/sculpture?
Find good references of Light. What I like to do is use the anime itself as a good reference for a Light. Also it's good to know what mood you want to give off in the drawing. It'll make it more visually appealing.

What attributes, clothing and/or scenarios, do you feel are essential to include in Light Yagami artwork?
His red eyes. I normally work with graphite pencils, but this time I added charcoal pencils into the mix. I wanted darker tones, so those red eyes could stand out. I also wanted the tone dark to give the drawing a dark vibe. Of course I had to have the smirk smile of his and the Death Note.

Is there more to recreating Kira visually than the outfit? (Expression/stance/slogan etc.)
Yes there is. I don't really want to quote another artist, but in this case it's the best answer I can give. Get his personality. It has to come across no matter what. Also get Kira expression right...either it's him writing names in the Death Note, doing the evil laugh or even eating a bag of potato chips. Having his expression right helps recreating Kira visually.

What, in your professional opinion, are fundamental tips/advice in producing art that's recognisably Kira?
Use good references and have them at a decent size. The larger the better, so you could zoom in on certain details. Also get all the references you might need beforehand. It's better to have references before you start, so they are ready for you to use while you are drawing. It’s a huge time saver.

What are the common noob errors made in drawing/modelling Light Yagami?
Not getting the details of Light right...like his eyes, hair, clothes, expression, etc. Having a reference from the anime, manga or even action figure is a great way to make sure you have the right details of Light.