If you are talking strictly comfort, you will need to rework your seat or buy a new one.

But for "swamp ***"
I wear a pair of "compression undershorts" and use a “HD Circular seat pad”.
Several companies make them, from $30 for a pair of Under Armors to $10 Starters from Wal-Mart. But they all work.

It stays above 95 degrees where I live for 4 1/2 months a year here. During the summer when my buddies get off the bike they are dripping wet in the *** area and I'm dry as a bone.
The HD Circular seat pad also keeps the seat cool enough to sit down when the bike has been out in the sun during one of our stops to cool off. My buddies all scream about burning the gonads when they sit down.

Here's what I know:
Sheep Skin is warmer in the winter and cooler in the summer.
It looks like crap (to me, personal choice) and it better be easily removable because it ain't worth a crap in the rain....and we get sudden thunderstorms all summer.
It will help with swamp ***, but I'm not so sure about adding comfort. It should help a little.

Gel Pads were actually started being used on motorcycles to reduce vibration, not necessarily comfort as most people think. They may help a little with comfort but not what you are thinking.
They will get hot in the sun and will stay cold if the weather is cold out.
I've had gel pads installed in a seat and was not impressed. My installer actually put a layer of insulation above the Gel Pad because he said I would not be able to sit on the seat when left out in this Texas summer sun.

 

Sheepskin is the best. Pads are comfy, but they don't breathe; you get sweaty ***.

 

beads and cycleing shorts. get off a few minutes every couple hours. if you dont have time to stop and relax a little every couple hours you may have the wrong pass time.