Stairs and slabs that use the wood blocks rather than the log blocks, and have the bark texture on all sides (stripped logs also have a stripped wood, since the log still has an end to it).

So what you mean is full-bark stairs and slabs?
How would one craft these? 1 log-stair or a 2x2 of log-stairs -> 1 or 4 full bark log-stairs? (Same for slabs.)
And how would we determine what direction the bark texture would go on the sides of these stairs/slabs?

Should the inside of the stairs still show the growth rings or the bark texture as well?

Well you can craft bark blocks already so just use these?

So stairs and slabs that are both completely full-bark like this and this?

Full album including concepts from #13

They would be crafted the same way the log ones are but using wood blocks.