Thinking critically is more than simply criticising. And it's going to take more than criticism to evolve legal standards of animal welfare.
Take a look at this essay: Why animal welfare ought to trump consumer freedom of choice in some cases (http://researcharchive.vuw.ac.nz/xmlui/bitstream/handle/10063/5113/paper...)
There is no doubt that animal welfare is a subject that is demonstrably near and dear to the hearts, minds, and pockets (in many instances) of the public. However, it's also clear that opinions about how animals "should" be treated vary enormously, to the point that the public opinion has at times been referred to as "polarised".
So the question is "where to draw the line"? Personal opinion is relevant, but understandably, any opinion is strengthened when it is "authoritative". With due respect to personal opinion, there have been times when essays, opinions, and submissions, amounts to little more than just another emotive opinion when the word "should" - or synonyms like "ought" and "supposed to"-occur without some supporting credible research, law, or similar authority.
In theory, our utilitarian system of governance recognises the benefits in "evidence-based decision-making" ; and critique (not just criticism) that demonstrates balance, objectivity and a broad consideration of relevant issues/outcomes associated with proposed changes.
With those benchmarks in mind, have a look at this essay. Whether you agree or not with the contents of this essay which has been put up in the public domain, it does serve as a useful exercise in assessing balance, objectivity and practicality. You might also find it interesting to start by counting the "shoulds" and "oughts", and then consider what difference would be made when any argument replaces the "shoulds" with "coulds".
For comparison and interest, and to assist with consideration of "balance", you might also like to look at the following websites: