Hi Jordi, thank you for your review! Your honest review are important to know our strength and weakness, and how to make our tours better.
In regard to Perak Tong (cave temple), it is never listed in our itinerary (but it is in your Lonely Planet). As for Kellie's Castle, John did asked your opinion and he was told to bring you to the best places of interest, which he did, customizing the tour and went to Gua Tempurung which is actually much further away from the castle, and some small stop along the way, soya sauce house and trying the King of Fruit - Durian.
We planned all of our tour to be 8 hours long as we noted any time longer than 8 hours, our guests will start to struggle in the hot & humid Malaysian weather. From our record, your tour started at 8:00am and ended at 4:20pm (with about 10+ minutes of restroom stop at your hotel). The feeling of shorter duration than expected is actually a great compliment, as the saying goes "GOOD time tends to feel short... and the horrible ones feels like a lifetime"!!!
8 hours feeling short means you are hunger for more! So if you're available, we also offers day tours to Taiping, Kuala Kangsar, UNESCO Lenggong, Sitiawan, Teluk Intan, Cameron Highlands, and if there's more time & days, we can even plan more for you.
We will advise John to reconfirm with his guests about customizing the itinerary so cases like yours will not happen. Thank you again for the writeup and hope to see you, maybe in the near future!