If you want to move to a nearby country for lower costs, Philippines is a good choice given that the number of English speakers is likely to be higher while offering possibly even lower living costs than Thailand or Malaysia. Philippines also offer easy to get visas for retirees.
Now the problem is that you need to move to a society that you have not grown up in, and not likely to have spent any significant amount of time living in (unless you have worked there or was born there before moving to Singapore at some point in time). Some Singaporeans can adjust and have adjusted (congratulations, you achieved successful geographic arbitrage), but many find it difficult to. Again, if you are new to the place, your friends and family are hundreds or thousands of miles away (OK, some of you might not care about them). If your wife is native, it is easier to adapt.
Still, making such a move is quite a big leap, and you need to have backup plans if things don't work out as planned. If you decide to back out, you need to figure out how to move back to Singapore.