In case you wonder why I lean more towards text emails rather than beautifully-designed emails which use lots and lots of images, or with text within images (which also cannot be copy-pasted), this screenshot of an email I received from a non-profit shows why:
Images are usually blocked by your recipient’s Yahoo/Google inbox, which means they have to take an extra step to unblock images to read what you wrote. Most people won’t bother, and will just click away, or even delete it without reading.
Also, most text that are within images are extremely small and hard to read, especially on a phone screen.
Which brings me back to “What doesn’t get read, doesn’t get sold.“
Make it easy for people to read and make it easy for them to take action. Having a normal email that doesn’t look like a marketing brochure can actually help boost your fundraising. Which would you prefer? More effective fundraising, or a beautiful email that doesn’t get read?