Popup Advice

Thanks to all of the kind and generous folks who respond to my and other posts!

I really don't like popups, but I know they help to get more signups for my newsletter mailing list, so I am considering using them.

I am therefore looking for the best popup option for my Website. I have several lead magnets, and would test them.

The question is what popup option to use.

I really love exit-intent popups, but once I found out that they don't work on mobile devices, I disabled them.

As I understand, there are several other popup options.

One is based on how long the visitor has been on the site. This seems to be the most reliable option, but they do interrupt the visitor's experience. Theoretically, if my offer is good enough, they won't mind.

Another is based on how far they have scrolled down the page. The flaw I see in this is that if someone comes to the site, and just scrolls 20% down each page, and the trigger point is at 30%, then they'll never see the popup.

Yet another one is based on the user having X seconds of inactivity. This seems kind of "iffy", but it might work well.

The final one I know of is when the page loads, and I don't think that's good.

In order to avoid popups, I have placed my click bait on the top 20% of the page, requiring no popup.

So, my questions are:
1) Shall I use a popup?
2) If so, what protocol do you suggest?

Please give me your advice based on your personal experience.

Thanks a lot!