Good start Francesco ! I love it!
My suggestions:
1) Would be better to sharpen the spike of the pike with fine sand paper to confirm these weapons are dangerous, simple to do.
2) With these quiet simple coat of arms and the heavy engraving, also to 'almost' totally remove the coat of arms on the front side to keep a trace and paint as free hands as I learned a few years ago that colours were not added and sewed ver the background colour, but in the tissue; this seems too strongly visible here for this figure.
3) Question: are you planning to add oil painting as you seem to suggest: an acrylic undercoat? I am curious for myself
Good idea to start with the back side to experiment ...
Note: considering my age and later start in figure painting (5 years ago) and health alert this year (bypass), I am only painting one selected side of my flats, in order to double my painting capacity in diversification ! (but this is a personal decision)