A newsletter that makes donors happy is never really about the organization.
It's really about the donor's self-image, sense of pride, self-esteem; about feeling the pleasure of pitching in; expressing their values; doing something about a problem; getting a spirit-expanding quick shot of dopamine because "I did something for someone else and my human evolutionary software rewarded me!"
Like your thanks and welcome kit, your newsletter is a HUG you send into the privacy of your donor's homes and hands several times a year. The newsletter is a plush toy. It throws its cute arms around the donor and hugs tight!