1. Don't come in when you're pissed off. Take some time to cool down. When people are angry in here, they don't listen to the very useful advice and info we give them. People often storm off while I'm explaining to them step-by-step what they need to do.
2. Read everything we send you carefully. More than once, somebody's come in holding a letter that said "do Action X, otherwise Result Y won't happen" and they're wondering why Result Y hasn't happened yet. Turns out they didn't do Action X.
3. Don't expect every federal employee to know everything about every department. You're setting yourself up for a letdown. Citizenship and Immigration Canada likely won't know how to help you fill out your Canada Revenue Agency forms. They'll likely know where to send you for answers, though.
4. Bring your primary documents and identification. Your provincial birth certificate is the most important document you have, and it establishes you as a citizen. Be ready to present it. For those born outside Canada, bring your Citizenship card. In either case, bring a provincial ID (license) and Social Insurance Number card as well. No employee is going to risk his/her job by circumventing document requirements.
5. Expect long waits and processing times. These two things are partly due to some things every citizen wants. And that would be lower taxes and government accountability. We're always understaffed because hiring more people would mean raising taxes. There's always long processing times because we are expected to be held responsible for any and all decisions made. So we need to track down original documents, we need to document everything and often need the approval of a management team. All that is so we don't give an undeserving person some public money, and nobody likes that.
So I guess I'm done ranting. Just try to keep this things in mind. It makes things more pleasant for you and us. That being said, the government's never going to be perfect. But if you have suggestions, write them down. Don't yell them to the receptionist, because he or she already knows what needs to be fixed. The truth is, the public has more power to effect change than the lowly employees have.