hi carol,
good questions! you can do a reading using only the major arcana or you can combine them together with the minor! The major arcana are a stronger influence so when you have alot of them in one reading combined with the minor, then the influences are in the hands of fate and not your own, whereas if there are more minor arcana in a reading, then you are more in control of the outcome, see what i mean? and whenthey are near a card with like meanings, it confirms it more and makes it stronger!
the next three cards are set on top of the last three and read the same way, you keep going that way until they don't make sense, then the reading is over. That is why some of the readings i have done are longer or shorter depending on the question, You can usually feel it when there are no more answers anyway by your intuition.
As far as the 2 and 3 of wands, i agree with you, they do look alot alike! the diffence between the two is this: in the two of wands he is holding a sort of crystal ball, to me anyway, which tells me he is looking back to all the experiences from the past , because of the way he is facing, see what i mean?
in the 3 of wands he is looking over a barren land and facing backwards, so to me this means he is longing for old friends and things from the past that completed him. i hoped this has helped , if not let me know! also, anyone who needs extra help can im me anytime, if i'm not there i will get back to you!
love and light,
samantha