I wouldn't worry about revving it to 5000 RPM to get on the freeway once in a while. On Honda's, you'll only experience overheating if something brakes (radiator, radiator hose, water pump, etc.) or if you're pounding the sh*t out of your car (redlining it for 5 minutes straight).
Also, if it's 100 degrees outside and the car's moving, you should be fine. If you sit there in a hot parking lot (not moving) with the A/C on, you could overheat your engine so try not to do that for any longer then 10 minutes.
You might want to read this-->
http://www.aaasouth.com/acs_news/summerdrive.asp They are just making suggestions to keeping your car safe for the summer, including overheating.
-Ducky