@chicago123 diamond shrinkage syndrome (DSS) is what we call it here in PS-land.
as long as nothing else shrinks- the money tree needs to be watered, not forgotten to dry up and die!!!! LOLOLOLOL
If the wedding eternity ring is changing to 0.15pt each, I would hold off any other changes to the 3 stone. once that ring has been changed, you can then assess/ appreciate what the wax model of the different styles will look like.
And, because you are getting the wedding band re-set and you mentioned that you thought the 0.1ct stones might be too big.........
Would you consider to have the eternity ring in the true sense of the style- ie not have the baguettes(?)/ bar in between the other stones. Ie all the round stones touching? If so, i would look at getting the stones as 0.1ct each or potentially 0.05ct each stone.
have that discussion with the jeweler in terms of cost.
of course, you are in a diamond jewelry forum and we are nuts, here... we just giving you more options!
Sorry if that put you in too much of a head spin.