Swat valley best option with family, Roads almost good for Cars, rather perfect, places to visit, Miandam, Bahrain, Kalaam, Mahodand lake, Osho forest, Marghzaar again a beautiful place to visit, Malam Jabba beauty on earth, and finally Kumrat valley, it's beautiful, once you reached Kumrat, then decide to visit Kalaash valley, not too faar from Dir, Through Lowari tunnel.. Road is good, just a patch of 4/5 kilometers, not good but fine to drive.. From Oyon up-to Bamborat or Ramborat it's Jeep track, I'll never recommend Sedan if owned..
Kelash festival starts from 11 May, big crowed expected this year..
I visited all the places mentioned above, from March 19 to April 02 2019
Machine Land cruiser 4500, Average speed Motorway from Lahore to Rashkai 4 hours...
Swat valley approx Average speed 45/60 km per hour
Oyon to Bamborat Kalaash 20/25 km per hour..
Hope I've answered your question