I agree that this would be a helpful feature.
Some of my notes are in Khmer (Cambodian) alphabet, which can include vowel symbols above and below consonants, taking up a lot of line space. Because Evernote doesn't provide the ability to expand the size of a line (or space between lines), characters on one line sometimes overlap characters on the next line. In the attached example, I've circled a bit where there could be overlap, but fortunately, the horizontal spacing worked out to avoid the problem. I'm not always so lucky!