Depends on what you're after. It pays to know exactly what you want.
I'd suggest go DIY. The original cover is only stapled on underneath, it's not hard to remove those staples and slip something over the foam. You should be able to get everything you need from an upholsterer (scrap table) for under $20. A small light duty staple gun is all you need to staple everything back on.
If you merely want to achieve allover softer bum-pamper effect - inserting a thin (5-10 mm thick) medium density foam layer already creates a noticeable effect without distortion.
If you're after changing the seating position, eg slight rise the back of the bum = slightly increased lean-forward body / shortening distance to handlebars, inserting a pre-moulded 3D-gel-silicone bicycle monkey-butt-saddle-pad can achieve that easily .... including a centre groove to air the crown-jewels.
GEL Silicone Bike Bicycle Cycling Soft Comfort Saddle Seats Pad Cushion Cover US | eBay
Bike Bicycle Cycle Seat Saddle Black Soft Cushion Extra Comfort Gel Pad Cover US | eBay
Looks like the install would be pretty similar. The sargent diy heated seat only draws 2 amps too.This sounds great. But I am too chicken to mess up my seat. I had always wanted a heated seat. I assume most of the install would be similar. Has anyone tried the diy heated seat?