But, just to be totally nitpicky, the designer does have the right to forbid public display. I can't imagine why they would, but public display is one of the rights that the copyright owner has.
US Copyright law defines "public display" this way:
"To perform or display a work ?publicly? means ?
(1) to perform or display it at a place open to the public or at any place where a substantial number of persons outside of a normal circle of a family and its social acquaintances is gathered; or
(2) to transmit or otherwise communicate a performance or display of the work to a place specified by clause (1) or to the public, by means of any device or process, whether the members of the public capable of receiving the performance or display receive it in the same place or in separate places and at the same time or at different times."
Again, the copyright owner could choose to be nitpicky about this, and some have. This is particularly true if the design is of a licensed character or other licensed image. Some copyright owners are fine with your putting an image of the stitched design up as long as you clearly identify the copyright owner. Some don't want images up that are too detailed (i.e., they don't want someone to be able to recreate the piece using your image as a pattern) or that aren't somehow rendered unusable for nefarious purposes.
The copyright owner has the right to control public display of the work. Most are not going to have issues with the situations you mention.
I think it's a bit more than that. Yes, these are subjective judgment calls--no doubt about that. However, I don't think it's true that profit is essentially the only thing that separates fair use from infringement. The actual fair use language in the law is:
"Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include ?
(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
(2) the nature of the copyrighted work;
(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
(4) the effect of the use upon the potential market for or value of the copyrighted work.
The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors."
(which is very similar to what you stated above) There's also some guidance offered at:
Also, to pick a nit, copyright law has a very specific definition of "visual art" which many patterns won't achieve. Things that don't meet the criteria for "visual art" can still be copyrighted, but there are some specific things that deal only with "visual art." Copyright law defines visual art as:
"A ?work of visual art? is ?
(1) a painting, drawing, print or sculpture, existing in a single copy, in a limited edition of 200 copies or fewer that are signed and consecutively numbered by the author, or, in the case of a sculpture, in multiple cast, carved, or fabricated sculptures of 200 or fewer that are consecutively numbered by the author and bear the signature or other identifying mark of the author; or
(2) a still photographic image produced for exhibition purposes only, existing in a single copy that is signed by the author, or in a limited edition of 200 copies or fewer that are signed and consecutively numbered by the author.
A work of visual art does not include ?
(A)(i) any poster, map, globe, chart, technical drawing, diagram, model, applied art, motion picture or other audiovisual work, book, magazine, newspaper, periodical, data base, electronic information service, electronic publication, or similar publication;
(ii) any merchandising item or advertising, promotional, descriptive, covering, or packaging material or container;
(iii) any portion or part of any item described in clause (i) or (ii);
(B) any work made for hire; or
(C) any work not subject to copyright protection under this title.23"
Best wishes, Ericka