I think that's down to personal preference ;)

Well because they are small sprites this detail is a little much...one pixel on this scale is a bit much.

It not supposed to look realistic or even semi realistic. However, it helps smaller sprites to stand out.

It makes it look like a soft gel sticker :D

Nothing that i didt consider but i always feels a little flat or to pretentious when i put it on. Metal is shiny but most of the time a consistent shiny edge makes thing feel unnatural...might try it when i got more textures under my hood.

The design is fantastic! One thing you could do is edge highlighting. I always did that on my warhammer 40k miniatures back in the day.

Here's a quick paintover to show you what I'm talking about.

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