Since animal suffering should be avoided, is veganism the best choice among the standard diet, vegetarianism and veganism? Seems like we'll never really know how much suffering the more "ethical" ways to exploit animals for food cause. Isn't it better to avoid supporting those industries altogether?
Under certain assumptions, it is possible for eating animal products to be morally better than eating vegan food. In particular, you would have to believe that positive impacts on the animal's life outweigh the negative aspects, also outperform the net effect of wildlife that would have been on that land no longer being there, and the sustainability impact. I've explored this in this blog post, and I suggest in that post that it is possible for eating meat to be the better option, but it probably isn't: https://interestingthingsiveread.blogspot.com/2018/12/veganism-may-be-net-negative-but-we.html
You'll get a different answer if your moral system doesn't equate morality with minimization of animal suffering.
Regan's and Francione's rights-based theories are worth looking at as alternatives, for example.