- Quiet motor drive - weddings & candids with the least disturbance and fast shooting speed
- AF - again, ability to get the shot off as quickly as possible
- VR - for shooting at slow shutter speeds where flash is verbotten
- TTL flash w/ matrix/distance - subject to background distance can throw off a simpler flash setup; you will need ability to do TTL/matrix/distance with an off-camera bracket mounted flash and the capability for bounce flash and light modifiers.
For lenses I'd pick either a set of fast moderate fl primes: 35mm f2.0, 50mm f1.4, 80mm f2.0 or a 28-70 f2.8 zoom. TTBOMK, you will be stuck with a zoom if you opt for VR - ironically, as zooms are slower you end up with lower shutter speeds and more need for VR.
Wide aperture lenses let you throw the background out of focus and let the subject stand out - a must if you want the bride to stand out from her cousin in the background (the one with his finger jammed up his nose to the third knuckle).
There is nothing of a practical nature to distinguish any reputable lens over any other when it comes to optical quality. Unless you are using a tripod and shooting a slow high-resolution film there isn't all that much difference in image quality between a good modern lens and a 1950's Argus Cintar. Heck, bad lenses are at a premium item these days among the large-format crowd - the supply is limited as they aren't made any more.
I think the feature list above puts you in the Nikon or Canon camp.
For candid weddings shot in B&W by available light an alternative is a Voigtlander or Leica rangefinder for the ultimate in quiet. For a lower cost alternative there are the 60's vintage rangefinders with f1.7-f1.4 lenses such as the Minolta Hi-Matic or Yashica Electro-x. With an RF camera you lose the automation that a good SLR system can bring to bear on getting a good shot in the least amount of time.
Image quaility can be excellent with TMax-100 or one of the Porta color films as long as you don't make prints much larger than 5x7. At 8x10 and above the added quality of MF becomes very noticeable.
For formal portraits I would stick to the MF and LF systems you already have.