The list below includes the discard outlets I see most commonly played and used in drafting cubes
Want a full deck of matching proxies, a single one-off, or a stack of tokens
One of 4 possible promo cards
So, when it comes to choosing between English and Japanese, it should really be simple - the latter is cheaper in most cases, the print quality is typically better, and in my experience, the pull rates are markedly better
Actually, there's no ethical or acceptable reason to make "proxies" to pass the light test, bend test, and other well-known tests to weed out fake cards because there's no ethical or acceptable use of proxies that requires the proxy to be as similar to a real card as possiblea Sharpie on a basic Island does the job just as well and without any of the legal and moral issues