I came back to Malaysia in 2019 after living in the UK for more than 20 years. To me, Malaysia is still the best.

At the moment, I work a UK company and salary is based on UK, so I can save a lot now compare to when I was working in the UK.

To be honest with you I nearly fell off my chair when I heard about your salary! £5000+ is a lot of money in the UK. The tax bracket is also higher at 40% if your pay is at that rate (need to be verified). The norm salary is between £30-40K for a senior managers position. The top 10% earns £60K and above.

In any case, I think you should move. No need to think long term. Just go for 1 year initially and see how you get on. I think for 1 year you can leave your wife and kids here in Malaysia. At least by doing this you are not tying yourself down to a number of years there and if you only stay for 1 year you will get the experience which may be useful when you come back to Malaysia.