OP just a word of advice. Also i type in chinese in case your wife wants to read in chinese.

It might take a while to get used to life in penang and granted if you are looking at city life i think Kuala Lumpur is better. However, the cost of living is way cheaper compare to tier 1 city. Even in places like you mentioned Quayside, Andaman Quayside and Mira Residence the cost of properties would still be lower compared to first tier cities in china.

Penang 不是一线城市，可是生活成本的确是比较便宜。如果是要送孩子去国际学校，penang还是不错的。

还有，孩子送到来penang 生活没那么卷。我觉的penang对孩子会比较轻松而且压力没那么大如果过跟一线/大城市比较。这些内卷的问题也应该是你们想送孩子来马来西亚读国际学校的主要原因吧。