Tres jolie mon ami
Thats near the limit of my French . The base it looks very professional in fact amazing.
I would not suggest levelling the colours ( plus the grains are completely different) it may be worth sealing the Beech wood with some Yachting type of wood oil Swedish wood oil is good; the oils for yachts are more waterproof since they are normally used on gaff rigs which have a leather saddle on the inboard end of the gaff which slides up and down the mast plus either lines of wooden hoops chafe the mast so the Swedish wood oil is pretty tuff.
If you are good at varnishing you could do a few coats of gloss varnish and then finish off with matt or satin varnish but unless you are good at varnishing it will not look good.
I would leave it as it is ! But the oil is much simpler if you want to seal it and you are not filling in the grain plus you could apply it with a rag so it goes on thinly and then you will not get runs or sagging.
I would either replace those screws with flat head made of brass and I would line the heads up if the existing one are brass possidrives or Philips(if they are not brass or stainless steel I would replace them then I would line them up so they are square when screws are visible it look much smarter when everything is in line .
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