Unless you rectify the water issues in construction aspects of the porch itself, the sustainability, longevity, and maintenance of any flooring flooring system and associated area construction will be in question (just like your wood floor and columns)unless you choose a system specifically made for an exterior application. With your porch in its current state, what comes to mind is a ceramic/stone solution made for an exterior application with membrane over mud-bed over menbrane construction and a drainage/gutter/flashing system (like at least Schluter Ditra/Kerdi or even better Troba/TrobaPlus with a BARA/BARIN drainage/gutter systems for porch/terrace/deck systems). as for tile product choices, a high quality porcelain is an excellent choice for decorative exterior applications. a high grade masonry sealer for the joints is advisable as well. The important thing here is to either: (1) fix the water coming in, or (2) use a system where water penetration is irrelevent. Please dont make the mistake of simply installing cement board and tile over the wood substrate to save costs. While it may last longer than the wood, you will still most likely get water penetration into the wood subfloor/framing system, which in time, will still deteriorate the underlying wood, eventually causing tile/backer board system failure. Nothing will last over a wood subfloor system over wood framing if you dont take the proper precautions. Here is a link that might be useful: Schluter Systems

Our porch is all screen except for the columns and the narrow frames of the screens. Our colonial is circa 1938 and whitish columns and arch accents were the way to go. But I painted the wooden screen- and door- surrounds a very dark green, not black, but a black substitute. It lives well. The screens and the frames, being all dark, tend to disappear when you are on the porch. My porch is entirely shaded, and I wanted some light out there, so I painted the back wall of the house a lighter color. You don't see the wall from inside, so there's color liberty for that wall. (my house does have kind of the camp/cottage/farmhouse look) If you like I can take a picture later.

It was not easy to track it down to be honest. But the rep from Koma was able to give me the name of a couple of distributors in the area and I made many phone calls to try to track it down. I called one of the distributors and she gave me names of all of the dealers within about a 3 hours drive and I called all of them. I finally found a distributor who sold to a building company about 45 min away and we paid one price for everything, including shipping & delivery. I think it was around $22/board. That distributor had 109 boards in stock and we needed 106. You can get them directly from Koma but they only sell in bundles of 220 or something and it was about double what we needed and didn’t make sense to pay that much and we didn’t know anyone who may want to buy the other extra boards. And you’d have to pay to get the boards shipped from AL where they are located. I will look and see if I kept any of the info for the distributors (but they may not be same in your area I guess) but the Koma rep (info on their website to call them) may be able to help you.

I don't like light colored flooring for a porch. My sunroom porch floor is a light color tile and it looks like an indoor product, not a porch floor to me. My house is a vintage house with dark wood trim, inside and outside, so a slate look is my likely choice. If you have a light colored exterior with a beachy style, a light floor might work but I wouldn't use it for a traditional style house