In these parts summer is 31 to 39C 5300ft and above, so it certainly makes a difference for planning. Accident statistics show that the overwhelming description by a pilot (commercial and private alike) of what went wrong was loss of power.
Robbie's are the machine of choice and account for two thirds of crashes, logical since they would be the most power constrained.
Expecting a manufacturer to solve a pilot planning problem is putting the cart before the horse. If you can't do maths or read a chart, you may as well just get yourself a machine which has a bit more puff under the cowling so it will have a greater chance of saving your backside.