should vs could

English as a Second Language English Vocabulary, Grammar and Idioms
1

Please can I use the following modals to express the unknown future?

  1. Next year by this time I could have traveled to York.
  2. Next year by this time I would have finished school.
  3. Next year by this time I should have collected my certificate.
  4. Next year by this time I shall/can have collected my books.
    Please I want to know which of them could be used, and wouldn’t be grammatically wrong. Thanks
2

To me, all these sound more natural as “By this time next year…”.

“By this time next year I could have verb-ed…” is possible, but “travelled to York” does not seem a sufficiently notable event, or sufficiently lasting achievement, to be a likely completion of the sentence.
I cannot think of a situation in which “By this time next year I would have verb-ed…” would be used.
“By this time next year I should have verb-ed…” is OK when describing expectations.
“By this time next year I shall have verb-ed…” is not very natural or common in modern English. To describe things that are certain (or as certain as the future can be) use “… I will have…”.
“By this time next year I can have verb-ed…” does not sound like good English.