I haven't heard of the 25 rule before. It seems to work for 6 and 7 inch risers but digresses from "my" rule of "rise + run = 17. Tread would be 1" more (nosing)." With the 25 rule, you'd need to subtract 1" to get the run in order to mark out a stringer. With your "steps" being close to 36 - 40", they are more like individual landings, so the dimension rules are out the window, but there is still only 2 so the railing "should" not be required. And the lights should keep any concerns about safety in the dark, at bay. I wonder is multiples of "the ideal tread would apply...run with 36".
Then the end of the step is short of the depth of the chair and won't be a tripping hazard!
The paneling in the picture is typical of The Arts and Craft style (mid 1800's - 1910+) which was a more formal version of the US "craftsman" variation, and was gradually phased out by the more organic Art Nouveau style from 1890 - 1910++. Which in turn was replaced by the Art Deco style in the late teens,1920's and 30's. Your architectural history lesson for the day.
Looking at the red panels, I see there is a gap at the top (and sides). Could it be shimmed up tight to the top, to keep away from putting a moulding up there? The sides would get covered by the cove you are putting next to the columns. By pushing them up it would also give a little more space at the bottom, above the outlets! What is there now, about 3/4"? Ideally you'd need about 1 1/8 - 1 1/4" for a sill, for proportions. You could very carefully trim the top of the cover plate...but don't tell anyone that I said that. I'm guessing the 29" steps up to 41" below the stairs. Ideally the seams between the Sapele panels would be covered by strategically placed moulding such as a stile if the paneling, or similar, in #432 was used.
Looking at the outside corners of the columns... You could carry the design of the cove moulding that is in the inside corners by making a beefier than normal outside corn and running 1/4" coves on the edges and a 3/8 or 1/2" cove (same size as inside coves?) on the corner. See sketches. The over-all thickness of this corner piece would set the thickness of the base moulding. It will need to be shimmed out. Laminate a strip of Sapele on the back of the top for use on the columns and scrap wood for use on the walls. The scrap wood will get covered by the next moulding in the stile and rail detail.). This will give you the base thickness you need to do the stiles for the paneling as well. The stiles could be flat boards with the smaller of the two cove bits down each edge... or for ease of installation, use flat boards and run a separate cove moulding around the inside of the stiles and rails. The stiles and rails could be slightly thicker than the the dimension of the cove moulding.
IMG00335-20130622-1446.jpg 212k .jpg file
IMG00334-20130622-1424.jpg 187k .jpg file
Play with the widths of the "panels" to try and have the outlet either centered on a stile (make it fatter around the cover plate) or on a panel and try to cover the Sapele joints. The center panel (or pair) could be wider than the flanking panels. Just make it symmetrical.
The inside cove moulding would stop on top of the sill. The sill could have a small round-over on the top edge (1/4"-ish) and the 1/2" cove on the underside to keep the theme.
Or something.Edited by just jim - 6/22/13 at 12:50pm