The revelation is that I did all that colouring on a single layer.
That I didn't spend 45 minutes fussing over it to get each line clean, smooth and perfect. I embraced a little roughhousing with the picture, a little relaxation from fastidious smoothed linework, and it really worked out. That all feels like a genuine artistic breakthrough to me.
And yeah, the spell effect I did but it looked kinda rubbish and it'd take ages to get right so I nixed it. Oh well.