I think stomach separation is very common in pregnancy and if you can get it fixed, good for you.
It seems my problem was that the muscles had not only separated, but also stretched, so sewing them back together would not achieve anything. I will always have a belly bulge.
I have had my umbilical hernia fixed, three days ago. I still have the bandaid plaster thing on though, so not sure what it looks like yet.
Keep us up to date. I hope you get the answers you're after. Let me know if you have any questions about the hernia operation.