Hi Sashakins
To be honest I enjoyed all the parts of Malaysia I have visited...Langkawi and Sabah probably most of the beach resorts....KL and Taman Negara of the non beach destinations.
Hotels in KL ...the Mandarin Oriental followed closely by the Sheraton Imperial.
In Sabah we stayed at the Tanjung Aru...no great beach as such but easy access to beaches on nearby islands. However I think I'd be happy at any of the Sabah hotels we tend to see in UK brochures although I found the Rasa Ria (Tanjung Aru's Sister hotel) a bit remote for my liking.
In Langkawi I liked the look of the Tanjung Rhu...on a good beach. But we only had a meal here and used the beach...we were staying at the Sheraton Perdana a fine hotel but on a poor beach.
Pangkor was on a good beach but I was a little disappointed with the hotel.