My fiance proposed with a ring from his mother's family. His great-grandfather bought it for his great-grandmother as a "just-because" ring in the 1930's. It's a three stone ring and all three stones were originally flush with one another in a platinum band. The center stone is .2 carat and the sidestones are .1 carat each.
His grandmother got the ring in the 1950's and had the center stone set higher in a square basket setting. I got the ring in this form, and a photo is below. Everything looks bigger in the picture, sorry it's not great.
When my fiance got the ring, he was given permission to change it however I wanted. I'd love to be able to keep the original stones, but the center stone is so tiny that I've decided to remove the basket setting and put in a newly-set larger round stone. I'm keeping the rest of the ring and side stones intact. I don't want anything too big, I don't want to overwhelm the ring, but I do want the ring to look less like a three-stone and more like a solitaire with side accent stones. So I am considering stones ranging from .7-.9. Any thoughts on whether I should stick with the bigger or smaller end of that spectrum. I'd also love to see if anyone has a ring similar to the one I am changing it to. Thanks!

His grandmother got the ring in the 1950's and had the center stone set higher in a square basket setting. I got the ring in this form, and a photo is below. Everything looks bigger in the picture, sorry it's not great.
When my fiance got the ring, he was given permission to change it however I wanted. I'd love to be able to keep the original stones, but the center stone is so tiny that I've decided to remove the basket setting and put in a newly-set larger round stone. I'm keeping the rest of the ring and side stones intact. I don't want anything too big, I don't want to overwhelm the ring, but I do want the ring to look less like a three-stone and more like a solitaire with side accent stones. So I am considering stones ranging from .7-.9. Any thoughts on whether I should stick with the bigger or smaller end of that spectrum. I'd also love to see if anyone has a ring similar to the one I am changing it to. Thanks!
