Do not be concerned.
He is falling asleep after all.
Taking 1/2 hour to actually FALL asleep, is fine.
My kids did that too, as babies.
They were fine.
They didn't complain.
They would "wind down" and babble to themselves, and then fall asleep. It was fine. They were fine. It was their rhythm of falling asleep. I knew that.
I did NOT interrupt "their" going to sleep rhythm/process at all. Because, THAT is how my kids fell asleep, as babies. And it was fine.
Your baby is fine.
He is falling asleep.
So what if he takes 1/2 hour to do it?
He falls asleep, on his own.
Myself, I don't fall asleep as SOON as my head is on the pillow.
If I were you, I would not mess with his bedtime or routine. At all.
Let it be.
It works.
And your baby is fine.
There is no need, to go in there while he is in his rhythm of falling asleep. Just let him be.
That is not a problem, him falling asleep in 1/2 an hour.
And he wakes between 6:00-6:45. Well that is when my kids wake too, in the mornings. They have ALWAYS woken up at that time, in the morning.
I don't mess with it.
As I said: BOTH my kids were like that as babies, too... .taking 1/2 hour or so to actually fall asleep. I knew them and that is how they fell asleep. And they were FINE. IF you interrupt him in that process, you will keep him awake and mess it up.
I... did that a couple of times, per my son, when I didn't know better. And then it would actually WAKE him and then he would NOT fall asleep. So then, I just let him be. And he was happy, babbling and what not, playing with his crib toy, and he would fall asleep. Sure, it might have taken 1/2 hour, but so what. He would fall asleep, after that. That was HIS routine.
And he did it that way for naps too.
Sometimes, my son would actually just want to stay in his crib, and he was happy as a clam, even if/when he was awake and babbling to himself. I didn't interrupt him.