I’m pretty sure my ideal translation would be mine alone. I don’t know why everyone’s so quick to embrace a less-is-more approach, but it’s likelier I’m the one being unreasonable by
wanting it all 
.
My ideal (read: Ultimate) translation:
A Polyglot. Columns would include the major ancient versions still used today by the Easterns, as well as other versions that can provide insight. Off the top of my head (so please don’t take omission for rejection), these would include the LXX (critical greek in the NT), the Coptic, the Ethiopic, the Peshitta, the Slavonic, a critical Hebrew, and (of course) the Clementine. These would be interlinear translations, including the original language, a phonetic transcription, and a literal rendering preserving word order. Beside all these interlinears would be the actual English version, where I would lean towards a literal translation of the Clementine (in paragraph layout). Manuscript variants of note within each tradition would be footnoted at the bottom of each column.
Cross-references and liturgical cycle indicators would be on the bottom of the running translation, since the presence of the other columns would eliminate the need for variant notes here.
I like footnotes! I like lots of them! The Haydock has some real gems, but sometimes it digs a little deeper into minutiae than I care for. The original Douay has some important apologetic notes. And of course, our great fathers, doctors, and saints have produced quite a bit of insightful exegesis over the centuries. There’s also a lot of overlap between these commentaries, so naturally this wouldn’t be a “just throw it all in there” moment - But when a unique pious perspective is available, I’d rather see it included than ignored. On the whole, I’d like them to lean towards apologetics and devotions. These footnotes would be on the bottom of the page spanning across all textual columns.
Book introductions would be encyclopedic, including the history of the text itself, a summary of its manuscript traditions, and the role the book as a whole plays in the life of the church.
But wait, there’s more! A topical index, all the usual family-bible pages, the papal encyclicals regarding scripture, and plenty of full-color illustrations. Tables at the end include the liturgical reading cycles.
And: an apocrypha section. Pope Clement left it there “lest they perish entirely.” Whatever his reasoning for doing so, they probably hold more water than any dismissive argument for leaving it out.
I second Ron Conte’s points on the character of the translators and copyright issues, but I’d rather not get into a semantic argument about “infallible” vs. “inerrant.” When it comes to translating ancient languages into modern ones, it’s a hair I don’t think really needs to be split.
Oh, and I’d like this all in one volume please. The paper will be thin and the font will be tiny, but that’s what magnifying glasses and TLC are for. Leatherbound and gilt edges, if it’s not too much trouble.