"My friend has humor."
Translation:Ο φίλος μου έχει χιούμορ.
We would say ο φίλος μου είναι αστείος,πνευματώδης ή χιουμορίστας, χιουμοριστικός is not normally used for people
In English would it not translate better as " My friend is funny" or "my friend has a sense of humour"?
Yes (sorry, I get a bit repetitive on these types of sentences), you can't say "my friend has humour" in English. This is a wrong sentence. All of the 3 mentioned above (sense of humour, funny, humorous) should probably be included, with the first of these as the standard translation.