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Idling in gear won't "hurt" a transmission. The "slip" of the torque converter WILL heat up the transmission fluid, but this is normal. All cars have a transmission fluid cooler in the radiator, and sometimes an additional external cooler for heavy-duty applications like towing. Unless your torque converter has a "lockup" feature it's always slipping during normal driving and that's why automatics are less efficient that manuals.
Go ahead and smack that right pedal down anyway you want. As the airflow in the engine picks up the EFI will add gasoline as required. Yes, carburetors will too. The amount of power you ask for with your right foot won't damage the valves, or any other engine component at any rpm as long as it stays within limits. Ditto for the transmission, no need to back off, just plant that foot. Some high-output engines have a fuel cut-off which is engaged by the transmission during up-shifting to unload the drivetrain, but that's more for a F1 car than yours.
Each manufacturer's testing is a lot more severe than your driving, and its normal, un-modified power output allows it to be driven in any mode you choose between these limits. Remember that these limits include correct tire pressure, tread depth and size, as well as engine temperature, oil level and pressure. If you're making a TON of power for a long time, keep an eye on the gauges. Oh yeah, also keep an eye out for speed limits, cornering traction and radar too!
You will use fuel, brake pads, rotors, tires, clutch discs, and other "consumables" at faster rate but there won't be metal-bending damage.
Keep up the regular maintenance, go out and enjoy it!
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