Treat this as four distinct travel blocks
Use three nights in Istanbul, three in Cappadocia, one in Selçuk, one in Pamukkale and a final Istanbul night. This protects full days in the two largest sightseeing areas and keeps the long overland return visible. It also avoids pretending that Ephesus and Pamukkale are stops beside the railway platforms.
Book the Istanbul to Cappadocia and Cappadocia to İzmir journeys only after checking both airports and the road transfers. A direct flight from a Cappadocia airport is useful when it genuinely operates; otherwise a connection can consume the day. From İzmir, regional rail reaches Selçuk. The next train reaches Denizli, followed by local transport to Pamukkale.
Put weather-sensitive choices early
If a balloon flight matters, schedule the attempt early in the Cappadocia stay. Use another day for a valley route chosen for the weather and footwear. In Istanbul, keep interiors and neighbourhood walks flexible around queues and access. In Pamukkale, do not promise a sunset or a particular water flow.
Shorten by removing a region
With eight days, remove Pamukkale and return from Selçuk or İzmir. With seven, choose either Cappadocia or the Ephesus corridor after Istanbul. Do not save time by placing a balloon pickup immediately after an overnight coach or by visiting Ephesus with luggage on a late arrival.
The example total excludes flights, ballooning, major admissions and airport transfers unless clearly stated. Replace it with the complete bookings for the route.