#1, You could paint the side ,stain the side.I never do anthing with the sides.
#2, i can't help much with this one,but stains and oils need to dry plenty before top coating i'm sure.
#3,Yes from the inside out as handleing the outside full of holes is very fragile for one,Theres more reasons but some one else will chime in on that as i forgot what they are.
#4,I've used chinese saws where the top arm is stationary and the dw788 ,dewalt arm lifts up out of the way for easy threading of the blade either from the top or bottom,i'm a bottom feeder.Thanks for asking beginers questions ,Keep asking away that's why were here to make scrolling easyier for you !Welcome friend!!!!!!!!!