I have a friend coming out to visit at the start of March and we are going to see Mayalsia together, on the following itinerary
KL - 4th -6th -
Taman Negara - 6th - 10th - Trekking etc
Perhentian islands - 10th - 15th - diving, snorkelling, chilling
Just wanted to know if people think that is feasible in 14 days and where we should go to in TN and PI, any advice appreciated
Just by reading the message it looks like you're staying less than 14 days?
All looks pretty well planned, just take into account it's not that easy to travel to Perhentian from Taman Negara. You may want to do some research there.
Good luck and enjoy your trip.