I'm happy to see your point. Ok
Cheerful and pleasant really do not work in this sentence.
The phrase 'I'm happy to' doesn't usually mean that doing something fills the person with happiness. It is just a set phrase - a way to say 'I don't mind doing X/I'm going to do X'.
I'll tell my clients 'Ill be happy to post another copy of your invoice' - a polite way to respond to a request whereas actually inside I'm fuming that they are wasting my time AGAIN! Grrrrrrr..clients....grrrrr