Planning my next holiday in Thailand/Malaysia

[LukeGT]

My idea would be a trip to Thailand and Malaysia.
The duration is quite flexible but it's reasonable to consider 15-20 days.
The itinerary would be from Bangkok to Kuala Lumpur or VV.

I know pretty well BKK so i don't plan to spend time there, while i could consider to stay at least one night in KL (even for possible Do).

I know the area between the two capitals offers a wide range of places and things to do.
In the Malaysian area Penang and Langkawi come to my mind, while Krabi, Koh Samui, Phuket and Phi Phi Island are the first places i'm thinking of about Thailand.

Probably i'm forgetting / not considering other places, so please feel free to suggest me better/different places i should include.
On the other side, due to the limited time available i know i have to trim the destinations' basket since i can't think of changing hotel every day.
Which locations would you choose and why?

Remember also i'm considering trip from one place to another not using planes, so only trains/boats/rented cars/buses and tuk-tuk are my options!
This is a volounteer choice


Thank you in advance.
luke

[lee_apromise]

Pulau Tioman and Pulau Redang, how about these places?

[singaporu_kooku]

Pulau Redang is very nice, but it's closed during monsoon season. I like Kota Kinabalu, it is something different from what you see in Peninsular Malaysia, not to mention the opportunity to get close to Orang Utan in its habitat.

For something away from the beach scene, I would recommend Chiang Mai in Thailand.

For transport, you can probably try the Eastern & Oriental Express train from KL to Bangkok, but it will take 3 days, which may not suit your timing.

[LukeGT]

thank you lee_apromise and singaporu_kooku.

I've been in CNX and i really loved it. But this time i think it's quite far from my travel path.
About transport i plan to make some stops along the way.. i've only to decide where!

[MAN Flyer]

I like Kota Kinabalu, it is something different from what you see in Peninsular Malaysia, not to mention the opportunity to get close to Orang Utan in its habitat.

I second this advice.

I've been to Kota Kinabalu numerous times on holiday, as well as other parts of Sabah and Sarawak, and also been there numerous times on business. We love Sabah, and Sarawak, although we haven't been there as much as Sabah.

Go and see the fabulous Orangs, before they disappear.

[9V-JKL]

Kota Kinabalu as others have suggested is a great place but you'll likely have to fly, I don't know if you can take a boat.

Not sure if you like quiet places but if you do, Trang in Thailand is quite nice to just go and do nothing. It'll be land transport from HKT. About 2hrs I believe. Some great food there.