I work with NEFs that I open into PS as 16 bit Tiffs in Prophoto RGB. My files are intended both for family photobooks and for further editing of the best - plus these last ones will end up being resized to more than one size before their final output. I presently do not do any sharpening in Camera Raw (I use PS CS6) and remove noise after opening into PS where I convert for smart filters and use either PS's own filters or (mostly) the Neat Image plugin. I do not do any sharpening here as I have learned it would be best to wait as long as possible doing this.
I want to be able to do some localized sharpening (using the sharpen tool) and also to remove blemishes (here I often use the brush tool that also cannot be used on a smart object). Also output sharpening. I have to admit that I previously did all this (except of course the output sharpening) on the background layer (to minimize file sizes and also because I always keep untouched original files elsewhere) before further editing in PS. When I got some very noisy files from family members with less good cameras and found pixel holes and remaining noise in darker areas I even used the blur tool directly on this layer (on faces) before applying the sharpen tool where needed locally. This is perhaps vandalism from a professional standpoint but a desperate attempt to save these files if important for the family history.
I am sorry if the questions are dumb or disclose a lot of misunderstandings but my learning curve seems to become steeper and steeper with age.
Git