Great news! And his nights are getting better, too... settling on his own and such. I think if he does want some milk between 3-5, give him only 3 oz. to help him eat more at wake up.
I know it's hard, but try feeding him only at 7am, if that's when you'd like for him to wake... the more you offer milk at 6 or earlier, the higher the chances he'll wake then.
for A times, I would keep the first one short and by tired signs. The 2nd and 3rd nap can be pushed 2.15-2.20 mins. He is probably ready for bed at 6:30 with 3 shorter naps...
5pm could've been too early for a CN... he might've been more inclined around 5:30. If you'd like to keep a later bedtime, I would only do a 10 min CN at 5:30 and bed at 7:00. This is if his naps have been short all day. If not, just do a solid 3 naps.