Could you explain, or post a picture of "side boxing"?

do you Wainscott

Railing for stairs

Like this or is this dates for the below chair rail?

that doesn't date the home but that style is more traditional if your home is traditional then it will work

HI -- Laura -- Because of the upstairs railing you would need to start your plan of some picture frame moldings for that wall from that point to tie in . Get a finishing carpenter in to do that so it will look balanced . I think I have something on my ideabook ( pg 3 betsy burnham ) of a wall molding you might like - it's a bit more modern looking . For the spindles you could replace with some wrought iron or just paint the wood spindles a satin black for the look.