The brake pedal in my 06 Pontiac g6 seems harder to push than normal. Since the issue started, I've had the rear rotors and pads replaced, along with a control arm. For the first 10-15 minutes of city driving the brakes feel fine, but if I hit a bump while I'm braking, sometimes it feels like the ABS kicks in. I also found that the handbrake is easy to pull all the way up and hardly holds on a gentle incline. Is this a brake fluid issue or something else?
It's possible you got used to the feeling of the pedal with some air in the system. If the air was flushed out when the brakes were 'bled' this would account for the additional firmness you feel. As long as the brake booster is working and the brakes were installed correctly, the firm brake pedal is a good thing.
Your parking brake is another story. It is a 'self adjusting' type that should tighten up on it's own. See this forum post - http://www.g6performance.com/forum/showthread.php?t=15491
If you did the brakes yourself, verify that you followed the procedure correctly (ask what it is in another question here, or do some searching online). If you had a shop perform the work, take it back in. A barely functioning emergency brake is a safety issue, and shouldn't leave a shop in that condition.
I would have the front wheels bearings checked. A bad bearing can cause sensor misalignment and the ABS to activate. You may also have an issue with the power brake booster. The booster uses engine generated vacuum to assist with pedal effort. A leaking vacuum line may be reducing the vacuum and increase the pedal effort required to stop.