I think if the two styles are unified by the same paint, they will be fine together. Shaker is very simple and will retreat to the background as a design element. Use the same baseboard detail throughout as another unifying element. The stairs may prove a challenge. If you are having a contractor install the wainscot, make sure that the stair trim is discussed. If this is DIY, we can chat further. I'll monitor your post and jump in as needed.

Yes, I am planing on my husband doing it. He finished off our basement but has never put up wainscoting. The stairs do concern me... He is quite good at measuring and planning. Do you have any advice?

Sorry about the name thing, I could not see having 2 Facebook accounts... there would be nothing on his! By the way.... love the work you have done. The traditional Kitchen is that a soapstone sink? - Linda

The sink? Slate..custom made. So, regarding the stair paneling. Because the stair skirt is already in place, tucked up against the treads and risers, you don't want to remove it. Instead, remove the drywall from the wainscot line down and dig it out to about an inch below the top of the skirting (the "baseboard" of the stairs) Layout the panels and install 3/8" MDF or birch plywood in lieu of the drywall slipping it behind the skirt board. Glue and nail it on. Install 1/4"X 2 1/4" strips to the top of the "paneling" making sure to cover vertical joints. These run from top of plywood to skirt board. The diagonal layout of the plywood means a lot of wasted panel, but studs should land on 48" centers. The verticals should be glued and nailed in place. Now install 1/4"x 2 1/4" sloped pieces to butt to the top of the skirt board and the same at the top, glue and nail in place. Sand all the pieces flush at the joints. Install a wainscot cap trim and prime and finish paint. The same process can be done on the halls, but since the base board is removable, use 1/2" plywood and wider horizontals so the baseboard sits on the applied trims. i hope you understand my directions...it is a little hard without pictures to guide you. I'll stay in touch..and thanks for the compliments!

Oh! If the Shaker style is not working so good, you can add a simple panel moulding like a picture frame around each recessed panel. Local resourcing may be a challenge. Let me know if you want to go that route, I can maybe hook you up.