Hi - I should also have asked whether the top rim was bevelled or fired polished - the latter being a feature found perhaps more this side of the Channel - as I'm reading it you're speaking of the foot rim only - so how is the top rim finished - I can't see clearly enough partly due to colour but also angle of the pix.
Gilding, as you'll know, comes in two varieties - the cold sort which isn't fired and obviously less hard wearing - and the other sort that is mixed as a paste/fixative and then fired and lasts a tad longer ............. you'd imagine it would be easy to tell the difference from the point of view of thickness of gilding. Perhaps not in all cases though - and then there's age, use or non use - so not easy to be certain, but thickness you'd think would give the game away. Unfortunately, it's almost impossible to use gilding for reliable dating - it's been a decorative feature for eons.
C19 glass that has been gilded, cheaply, has often lost the gold colour, but the area of decoration can still be seen as darker and with a dull appearance - around rims, feet and parts of the body that once had the pattern. Think you're right about the French habit of going a bit OTT with their Empire gilding etc.
Suspect you know more about these things than me - I did for some time collect finger bowls - date wise ranging from the end of the C18 through to almost mid 20 (Walsh). Exceptionally rarely did I know the maker, and the odd occasion I did, it was only ever on first half C20 pieces - and have to say I never had a 'peacock' coloured example - it's a great colour. W/Fs did a 'peacock' apparently, which was imported via the Wuidart connection which was Belgian based and sold under the Wealdston range of designs - but since colours can mean all things to all men, it's an area difficult to get general agreement on, especially viewing the screen only, and the W/Fs version doesn't look quite like this 'peacock' and theirs was a century later anyway.
Quite honestly my opinion is that you may have to live with uncertainty on this one - you might try an antiques expert or dealer but I get the feeling that positive information is going to be thin on the ground with this one, but MHO remains that this may not be quite as old as we might wish.