my grandson is making a minecraft box (see photos). it is a cube that opens with a brass piano hinge inset in the back.  it is about 28″ on each side.
the frame is solid walnut.  the sides and top consist of 1/4″ thick squares (of sapele, maple, alder, cherry, oak) glued onto Baltic birch plywood.
there are some gaps (up to 1/16″) between the field squares and the walnut frame.
he wanted to keep the finish as clear as possible, so I was considering a blond shellac finish.  after the first coat (doubling as a sanding sealer), I was considering a wet sanding (400 or 600 grit) of the second coat of shellac to fill in the gaps (see the photo).  then another two coats of blond shellac.
another option I was considering was use of watco danish oil in a similar fashion.
what do you think?
instead of the first coat of shellac, should I use a separate sanding sealer (if so, what brand)?
what ‘cut’ of shellac should I use for the first and subsequent coats?
will the wet sanding blunt the whiteness of the maple?
would you use a different finish?
would you use a different method to fill in the gaps?
I don’t have experience with varnish (but willing to be taught by you if you think that would be the best finish).  I don’t have a sprayer, so the finish would be ‘clothed’ on or brushed on.
thanks for your advice.