Looking at your list of essentials, two comments and a suggestion:
First, there is no such nation. If a nation has first-world resources, that nation won't be cheap, full stop. There is no such nation. A high cost of living is the price of life in a first-world nation.
Second, you will need to prioritize your list and decide what you can and cannot live without.
My suggestion: live in a third-world democracy.
Before you throw a grenade at me, hear me out. I have a home in the Philippines, and here's my experience vis-a-vis your list of essentials:
- they speak English very well, having learned it as children from first grade. I have a niece there who only spoke English, whom I told to please learn Tagalog (the local language - it's FAR easier than English)
- it has first-world resources IF you live in the more well-to-do areas...and you won't need a *heated* swimming pool. But as for the library, it's either the bookstores (only a few of which are good for you) or the internet.
- Healthy food...surprisingly enough, if you go to the open-air markets there, pretty much all the food is grown without chemicals. For instance, eggs are not refrigerated there. Why? Because hens that have not been fed chemicals and antibiotics lay eggs that don't need to be refrigerated. Buuuuut you would still have to adjust to how local food is presented and prepared.
- Cheap rent: for you, they have it in spades.
- Corruption: it's very corrupt...but much of the corruption comes from the low tax base, which means that civil servants can't be paid a living wage, which means that they either take bribes or can't do their jobs. In other words, you learn to live *with* the corruption and make it work for you if you need. It's a lot easier if you can make friends who can help guide you.
- Safety: at first glance, it seems very unsafe, especially the roads with the horrific traffic. But ask yourself this: how many traffic accidents have you seen even in small- to medium-sized towns in America? I've spent all told perhaps a year in Manila, and in all that time, I've seen one - *one* - fender-bender there. Why? Because (1) the traffic is so congested that everyone drives slowly (thus more safely), and (2) cars there are not seen as toys, but as a means of livelihood - they're not used for thrill rides.
- A job...I'd suggest finding remote work. I would not suggest finding a job there. In today's world, you can find a job that will pay you remotely. I have a brother-in-law who was working remotely for a company in Los Angeles, but stayed in Manila for a year. Even at American minimum wage, you'd do okay.
- Ease of living - oh yeah, this is what is best about living there. Want a maid to come clean your home, do the dishes and laundry, six days a week? Maybe $50 a week.
- Permission to live there - it's only 30 days for tourists, so what you can do is to take a round trip for a day for about $400 to Singapore or Indonesia or somewhere close. BUT I've stayed more than a month before but the only place that checks your visa is the airport when you're flying out (whether one month or two years later), and even if they do check you, the current fine is P500, or about $10 U.S.
Lastly, the culture: it's very, very much like the Deep South (minus the constant undercurrent of racism). The people are kind and courteous to a fault, and respect for the elderly is a cultural requirement. You'd hear the word 'po' (pronounced 'poh') in almost every sentence said to you - it's the equivalent of 'sir' or 'maam' in their gender-*neutral* language.
The downside of living in a 3W nation, though, is this: it's unwise to live in such a place unless you know someone there that you can trust, who can tell you where to go or not go, who you can trust or not trust. I can do it because I have quite a few connections and I know the people, the culture, and - to an extent - the language (which includes a lot of Spanish, btw).
I guess what I'm trying to say is that as much as I'd like to tell you otherwise, you're never going to find a nation with your essential requirements, and I'm hoping to broaden your perspective a bit as to where you can safely and happily stay.