There are such grammar constructions that depend on the time frame, implied or expressed explicitly, of a whole sentence in the English grammar. One of them is 'would have past participle' grammar construction. Generally speaking, two first sentence of the examples are built in the real past time frame. The past indefinite tense is a grammar tense that references the real past time.
From the other hand, there is the usage of the modal verb 'will' with the construction 'have + past participle.' 'Have + past participle' is a structure to build the Present Perfect tense grammar constructions also. But, the former and latter in the special constructions are not the same in essence.
The construction 'will + have + Past Participle' bears two grammatical markers: the first is modality ( will) and the second is perfective meaning for the action (have + Past Participle).
As a modal verb 'will' is used, inter alia, to express belief (in semantical sense) or expectations.
The grammar construction 'have + Past Participle' informs that the action of a lexical verb happened before the real time of the sentence or the context , which is indicated by the tense (implied or expressed explicitly) of the main clause of the whole sentence or the time frame used in the conversation.
As we can notice the grammar constructions of the Future perfect tense and the Modal + perfective action are the same formally.
The modal verb 'will' has a past form 'would'. It makes possible to construct a grammar with the syntactical meaning of 'past intentions/expectations' with the form 'would+ have + past participle' that is the case of your examples. This grammar construction gives the hypothetical, unreal meaning to such phrases.
As Poppy mentioned correctly, the syntactic form of Conditionals differ from the grammar construction under discussion.
The modal verb 'would' is not used to express deductions about the past events, even in case of incomplete present time period. It is the modal verb 'must' that is used for expressing such idea. So, the third sentence of
examples should be as follows:
She is a very famous comedian. You must probably have seen her in a lot of movies these days.
As for your question 'Would it make sense if the verb' would'changed to the verbs 'might' or 'could?', a short answer is that any modal verb has got its own lexical and syntactical meaning. That is why a substitution of verbs brings a change of meaning of a sentence, not so significant in the case of this grammar construction. To understand this little difference of meanings among these modal verbs, I'd offer the articles from Collins dictionary.
You use would, or sometimes would have with a past participle, when you are expressing your opinion about something or seeing if people agree with you, especially when you are uncertain about what you are saying.
I think you'd agree he's a very respected columnist...
I would have thought it a proper job for the Army to fight rebellion...
I would imagine she's quite lonely living on her own.
You use might have with a past participle to indicate that something was a possibility in the past, although it did not actually happen.
Had the bomb dropped over a populated area of the city, there might have been a great deal of damage...
You use could have to indicate that something was a possibility in the past, although it did not actually happen.
He could have made a fortune as a lawyer...
He did not regret saying what he did but felt that he could have expressed it differently.