The term "veneer" in a masonry exterior wall traditionally refers to a 4" thick masonry "veneer", a drainage cavity behind it and a back-up wall of some kind. Another newer system is gnerally called a "thin veneer" where a 1/2" to 3/4" thin layer of masonry is directly adhered to a masonry back up wall with mortar. The former is normally for brick on wood framed or concrete block back-up walls and where subject to freeze thaw cycles because it allows for water drainage and differential movement. The latter can be used with stone and concrete or concrete block back-up walls in warm dry climates. On high rise buildings a 2" stone cladding is usually supported by an elaborate system of stainless steel pins and connectors with a cavity behind it. What are you building?

I don't think you can put a stone veneer on top of an exterior wood porch and steps. Wouldn't the stone crack with movement of the wood underneath and the wood and stone would contract differently in weather conditions leading to more cracks. I googled Poured in Place Concrete STeps: The average home requires a set three steps high by 4 feet in width. This method can be expected to cost, on average, between $400 to $650, not including the door porch area. Info on Precast Concrete Steps: A footing is still required for the stairs to rest on, Precast stairs are much cheaper than poured-in-place stairs, but are not as durable due to their hollow design. The average cost of a set of precast stairs that consists of three 4-foot-wide steps is around $200. Doesn't include labor costs or a porch area next to the door..

Your stone is a beautiful color. I would not paint it. You should consider painting the rest of the house as well as the garage door. The posts on your porch need a bit of beefing up. Can you replace the posts with cedar or have them wrapped in wood? Find a color that you like in the stone face and paint the house that color. Then you have a starting point to look for an accent color to paint the trim and the shutters. Also, changing the light fixtures would give this house a needed update. Something with straighter lines would work better with your architecture.

The stone is definitely not the problem. Easiest and quickest "fix" is to paint the trim (except around garage doors) something close to the darkest color (?medium/dark gray?) from within the stone -- but paint the garage doors and trim the same color as the siding. If the siding actually doesn't need to be repainted now, then don't; however, if the siding does need to be repainted, choose a lighter shade of gray (or another color from within the stone) for all the siding and for the garage doors and garage door trim and a slightly darker shade of the same color for all the other trim. The best, "fix" for the style of the house without a major overhaul of the house itself -- not a practical idea for a winter project -- would be to create a ground floor level entry centered where the current steps/stoop is located -- perhaps extending all the way to the back of the house -- and then put your steps to go up into your home over the garage within that new entry. create a porch in front with its ceiling at the upstairs floor level beginning at the new entry and in front of it alongside the garage to just beyond the front of the garage so you can have that porch roof turn at a right angle (hip corner) to build a shelter -- roof overhang -- over the garage doors. No need for posts in front of the garage if you build just an overhang with supports attached beside and in between the garage doors beneath the roof/overhang. You might consider "enlarging" the upstairs windows over the garage -- if not by actually enlarging the windows, then by creating a frame the same height around the real window and a faux window beneath it.