Certified copy of divorce decree is perfect (you'll find the original is on file with the courthouse anyway)
For savings, you genuinely just need the six months of bank statements. You don't need anything from his employer as that will just muddle things. As long as the statements are printed from the bank, you are good to go. But some people feel better having them stamped/signed on each page or a letter to go with them.
You can take out of the photo of the house, not needed.
Land registry is all you need (well, with the letter from your parents). Doesn't need to be certified.
We recommend only a couple of pages of evidence for contact. So if you've been together for 3 years, maybe have a year of contact on each page (3 in total), so maybe two shots per month. Whatever fits on a page worth. No need to send huge stacks of evidence. E-tickets will be fine if that's what you have. I would send a page or so of emails in addition to the Skype calls but do what you are comfortable with.
They'll know that you can't have anything firm from the registry office without the visa. All you need to show is that you are making plans - which is exactly what you have. So you're good here too.