Hi Bushy, definitely looks nice and clean pieces of timber to work with.
Wondering how thick the maple veneered top is as they are quite often very thin and extremely easy to sand through, particularly when doing grain filling.
If very thin i would suggest using a good quality black fountain pen ink applied full strength and wiped all over until dry, then 24 hours later wipe as much off with a 'just damp' cloth to soak back up as much as the black ink as possible. Don't worry too much as there will be lots still trapped in the grain you are trying to pop. If there is still a little bit of a dull greyish appearance just do a feather light sand with 240 or 320 grit to knock it back to natural.
Doing the same thing with ebony timber mate requires more delicate sanding and quire often ends in tears and lots of swearing.
Cheers, Waz

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