It's often difficult to distinguish certain letters when using voice modes on the radio. Especially if conditions are poor. The standard phonetic alphabet will help you to communicate your call sign and other information.
While there are several standards, the phonetics below are accepted worldwide. Other standards may be confusing. I know this as a frequent net control station for the 3905 Century Club net. The 2x1, 2x2 and other call signs don't help either. If I'm trying to copy a call sign and the last phonetic the operator uses is Ontario, I don't know if the last letter of his call sign is an "O" or if the station is located in Ontario.
How about cute phrases for you call? They may be fine to help another station remember your call. But it's not a good idea if you are trying to communicate under poor band conditions!