For this kind of application, it is essential to have those 2 features, layers and text capacity.

Would love to add templates and images and lock them so they can be marked up, without being erased when any text drawn over image is being erased.

I would like to be able to have drawing layers, so that I can have a sketch layer, pen later, shading layer, coloring layer, and so on. This would make it so learning digital artists like me do not ruin the whole art piece by attempting to color or line it.

essential tool to manipulate alternative versions, common to all the best graphic apps...please add asap