Magento 2: Best practice create model class

Question

First thing, I have a question on this topic Optimize load model memory

Then I have some questions for the best way to create a Model to load or save data to Database?

Could you please explain which of these options are bad and which are better.

1: Using Factory?

2: Using Dependencies?

3: Using Repository?

Or could you please suggest to me some other way that does it better?

Thank for any explanation.