Deck lighting

Not sure where to post this, but I am redoing my deck and had a couple of questions about lighting that hopefully someone might be able to give me some pointers. It is a very simple deck that is 12x14 (14 being parallel to house) with a one step landing from the back door (approx 3.5' x 5.5 ' almost centered with deck) and also a 7 step stairway down.

If I use the flush-mount low voltage lights for stairs (7W I think) with baffles, how many should I put on the stairs? Would lights on the 2nd & 6th treads be enough (bottom & top can't be used for lighting here due to structural reasons) plus one on the landing fascia? The treads will be 42" wide with 3 stringers. Since I can't center 1 light due to the stringer, should I use 2 on each tread which gets light? Also if I use the surface mounted lights (small circular shaped) on just the corner posts of the deck, will that be enough or too much. I am going for just kinda a background lighting where I still want to know it is night and candle light won't be overpowered by the artificial (besides safety with the treads and landing).