Recently spayed a very active (did I say VERY) 6 year old bitch after her last litter, the traditional way. No problems. I will continue to do it the traditional way. May as well remove everything in there she doesn't need.

The last bitch I spayed I had a Laprascopic Ovariectomy done and highly recommend it.

While it was $100 more than a traditional spay, recovery was only 24 - 48 hours. You did not even know she had surgery. No shaved belly, only 3 stitches.

We asked about the risk of pyro with the uterus still intact and we were told that there is no risk as the hormones are what causes it.

I think that you should do a regular spay on your girl. Her complicated c-section must have caused adhesions that can cause complications latter. Opening her up would give the surgeon a chance to check on that.
I have seen pyometra in cases where the uterus was left alone. I've also seen stump pyometra. So the risk is always there.

These pyos after spays are caused by remnants of ovarian tissue that are left behind; if you have a careful and diligent surgeon, post-spay pyos can't happen.