No relief for the legs, feet, and arms. On your feet, it helps to wear some kind of wicking sock so the moisture doesn't stay next to your skin. I'm sure the cold paks would help around your torso because they would be helping keep your core body temp down. Evaporative cooling is only really effective when the dew point is low relative to the air temp...low humidity. In the Southeast, it's usually humid, so that makes the hot air even worse, and there's not much you can do about it, really.
In this part of the country, when it's 95 degrees or above, it's just about too hot to ride for me, particularly since I've gotten older...seems the heat gets to me more than it used to. Riding early in the AM or late in the afternoon is about the only option...at least then the sun's not beating down on you, but the air temp in the late afternoon can still be stiffling. Staying on smaller roads surrounded by green things is a lot better than 4 lanes or especially interstates...the super slabs seem to add about 5 degrees to the air temp hitting your body. I hate interstate travel on the bike, and if time allows, will avoid them.
Cotton anything is about the worse thing you can wear, IMO, especially on your feet and upper body. Wicking garments are best, like backpackers use...any moisture will evaporate more quickly with those materials, keeping you cooler in the process.