Just an update, I stained all the wood and my wife finally has chosen the tiles to go on the risers. I am planning to install the straight section with the rectangular steps this week end. Just to double chech few things:
1) When cutting the back (long side) of the treads, we cut straight down (perpendicular) right? no need to tilt the blade by 5 degrees which seems to be the best practice for risers.
2) Use PL Premium or Titebond wood glue to attach the new oak treads to the current plywood treads?
3) Same question as #2 for flooring
4) Are 2" 18 gage brad nails adequate to secure treads while the glue dries?
5) Given the stair nose (for the winders) has a 1.25" overhang, I plan to cut all treads to maintain that 1.25" overhang. Is that too much of overhang given I don't plan to use the cove moulding? I'd like the look of the cove moulding but I have not been able to bend them enough to fit the curved steps.
6) I plan to put the treads in front of the riser because cutting a straight line in wood is easier than in tiles. But for the winders, I am not so sure given it is multiple pieces of adjacent flooring. What do you think?
7) The stair nose has a groove, but flooring only has a tongue&groove on the long side. I am planning to use my router to cut a tongue on the short side of the flooring to slide into the nosing. I thought it would make the connection more flush but not sure if that is worth to justify the additional work.
Thank you all again for helping me plan this out. Although I have already done a lot of work such as removing carpet, clean up the stairs, painting the side skirts, cutting the overhang, staining the wood, lots of measuring, etc... it feels like the exciting stuff is only about to start this week end :-)