Who said anything about "without shifting"? Please don't put words into my mouth.
Letters, digits and commonly used punctuation marks (like period, comma, parentheses...) are fine with me. They are commonly used in all languages and hence conveniently accessible on international keyboards too.
What I consider a bad design choice is the use of exotic punctuation marks like ~, `, {}, or \ for hotkeys. Since these are uncommon characters, many international keyboards do not make them available via shifting, but require another, rarely used mode key to access them. And most software designers seem to have reached the same conclusion: I don't see these used as hotkeys in other programs, including programs which offer a large number of keyboard shortcuts such as Altium.