Just remember if you ever give up your domain, whoever purchases it will now have your email as root-of-trust to EVERY site you ever created an account with.

Also, it can be pricey. If you have a .com/.org it is cheap, but I have a .io and the price keeps doubling every few years.

Also, it can be risky: and there is a very real risk that .io will be (rightly) reclaimed by the country that owns it and either seize the domains are really jack up the prices even more.

I use a .net domain that is automatically renewed via AWS and costs like $7/year.

Yeah I would suggest against using a ccTLD unless you have a strong connection to that country. Don't buy .io or .ai because they're trendy. Buy .com or .net or .dev or something else generic, or buy .co.uk if you live in the UK etc.

I have a .net which I register for 10 years at a time; and renew every 5-8 years in.

Don't you end up paying twice that way?

No? Your expiry just extends the number of years you add to the renewal.

That makes sense.