We're toying with the idea of replacing the tiles in our living and dining room to hardwood instead of homogenous tiles. 

I read that SG's humid weather may not be suitable for hardwood and maintenance is much more than homogenous tiles Is the cost also much higher?

Would love to hear from a house owner using hardwood for their flooring. 

Actually it would not be much of a difference, just that I think if you use tiles it will be easier for cleaning and also your house will be much cooler.
As in Singapore , the weather is humid and hot, tiles could help to release heat better. 
While on ur concern of maintaining the flooring, eventho Singapore is a humid country. If would be alright if you mop it regularly. No worries 

Hardwood does take some maintenance but it will look definately nice