We want to change the tariff plans and need your advice

Well, IMO none of the above. (I don't answer with it depends; ofc it depends! :D ) We're getting ready for our release, and we're gonna have a free forever / hobby plan which gives you access to a lot of things, but none of the enterprise features, also, not all the paid features. It's assumed to be just enough to attract the users to our product and also they can use it for trivial routine jobs which actually are plenty. So you should see what's the main reason you're providing this plan. After all, no one expects something serious and highly valuable to be free.

We have a free plan with a limit on the number of website visitor identifications. This allows users to see the full functionality of the product. Some people only need this and will never upgrade, but many people want more and are willing to pay for it. https://www.producthunt.com/upco...

It also depends on your side. The benefit of a free plan that's limited but still useful (i.e Zoom) is that you can spread to more people a lot faster. I don't think that applies to free trials.

I would not start with a free plan. Start with a trial and ask for payment. If you can't convince people to buy your product, you will not have a good time with freemium.