what are most crowede things that we should do early or later in day for less crowds please? going late may...
With 2n in Miyajima save the Torii gate before or after the daytrippers have arrived or departed. Don't miss it at night when it's lighted up and serene.
Take the ropeway and hike up to Mt Misen on a non-rainy day. Don't miss the Itsukushima Shrine and Daisho-in amongst some of the world heritage sites which are highly worthwhile.
My 2nd and o/n stay in Miyajima in late Nov 2017.
Most tourists go back to Hiroshima by dusk. It's a lovely time to walk around, but note that the shops will also close when the bulk of the tourists leave.
Check when low tide is so you can walk out to the base of the Torii.
Evening is nice when the lights are on. Morning is nice, too, before the crowds come.
Go up on the ropeway or walk up the mountain on Day 2. With 2 nights you'll have plenty of time to walk.