Hi,
Here are a few further comments.
a) I look forward to seeing him sometime. It will make me happy to see him. It sounds like there's a reasonable possibility that I will see him.
b) I hope to see him sometime. It would make me happy to see him but, compared to A above, it sounds less definite that I may see him.
c) I expect to see him sometime. It may or may not make me happy to see him. eg The prisoner expects to see the executioner on Friday.
Best wishes, Clive