Domain Registration

Have used porkbun and Google domains. They both offer all the bells and whistles you might need. Also, Google domain doesn't increase their price.

I use porkbun.

I use gandi. They only email when it's important. The UI and docs are updated. Never received a single spam till date. Didn't need to ever call support. All the PI is secure and never sold to third parties. Their price is ~20% extra but I like their no bullshit approach.

Yes I use it. Though, why do you need think so much about this? Hosting is important, domain you can buy from any site whichever is giving cheapest (though beware, they increase price from 2nd yr).