Saloon coaster won't go to Bamboriat.
I have only been to Bamboriat. Those areas are flooded every year and roads and bridges are damaged/destroyed.
During my trip to Bamboriat in 2016, we left coasters at Ayun (a place between Lowari Pass and Chitral) and shifted in Hilux (Toyota), even still at many spots we all had to get off it so it it could make a steep ascend.
On top of all that, there is a spot where two streams meet and passage to rumbor and bamboriat separate, there was a bridge, which had almost fallen in the stream but somehow locals had managed to use it. We all had to get off so that Hilux could cross it (it was a small wooden bridge). I don't think Coasters could go there.
Is it worth it?
Many people in our group were disappointed as it was nothing like advertised. Bamboriat valley is not completely occupied with Kalasha people, there are mostly muslims living there who are strictly following "Parda". Even Kalasha people have lives of their own. I don't know how much they could mingle up with you and invite you over.
Here are something you can visit when you go there.
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Kalasha Museum (A lot of items are at displayed)
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Sheikhanda Mosque ( Sheikhana is a valley next to bamboriat. You can hike up there.)
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Local Market/Shops for soveniers
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Kalasha Grave Yard (In past Kalasha would leave their corpses out in the open, but now they bury them. Still graveyard is something to visit)
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Talk to local kids (Kids there, not only have face of angels, but also sharp brain and good manners )
But I seriously doubt if family will find trip amusing especially without any festival.
I know a Kalasha Guy who is into tourism and one of those rare ones who would get you to stay in Kalasha people's home. If you want I can get you in touch with him.
