Why are you hugging the tank? If you find thank you need to sit close to the tank and it gets to hot for you, consider a tank bra.
For a normal riding position you should not need to hug the tank. Hugging the tank during commuting can be a sign that your are not comfortable nor confident on the bike. Which indicates that you may be too rigid in your riding posture. You should be squarely on the seat with feet firmly planted on the pegs. Your core should be providing the stability for your upper body and your arms a shoulders proving a lot of the steering input and a little shock absorption/stability. For some riders, hugging the tank can hider their ability to raise themselves off the seat should they need to if going over bumps or dips. Also hugging the tank can prevent you from shifting your position on the seat if you are riding twisties where the turns are a little sharper.
Does your bike sit in the sun all day? Parking in the shade or keeping a cover on the bike can help keep metal surfaces cooler.
Keeping the fuel tank full and out of direct sunlight as much as possible will help keep the tank a little cooler. Gas inside the tank can cool the metal as long as it is not subjected to direct heat
Why and how long were you traveling at 8k in third gear? One of the reasons you have gears is to reduce the amount of load and rpms on the engine. You can easily cruise at 40-45mph in 4th or 5th gear and still have enough power to pull away. Reducing your rpm speed can also reduce heat producing friction. At lower speed, low air flow can have an affect on cooling. The bike needs adequate air flow across the engine and through the radiator. So it is possible for the engine to have a little higher than normal temp in stop and go and slow moving traffic. Keep in mind exhaust temps at the engine can reach up 400 degrees faren. just a couple of feet away from you.
Good engine oil provides a good deal of engine cooling. So keeping the oil changed regularly and frequently is a good thing especially if you constantly run high rpms in high ambient temps. Also keep in mind that the exhaust runs under the right side of the bike.
When was the last time the coolant was checked/changed? you should at least change the coolant in the reservoir in between coolant replacement.
Coolant in the reservoir is not completely air tight and is exposed to air. In a pressurized system it is not. The ethylene glycol breaks down over time and becomes oxidized.