I ride both a non electric road bike and an upright electric bike. For the road bike I have a slim, firm, elongated seat. For the e-bike, because I sit upright and want the most comfort possible, I have a shorter, wider, more padded seat and a Thud Buster seat post. Everyone's tush has different requirements. As I like to say "Only the Butt knows". I would see if I could "try before you buy" at a local bike shop. Seat adjustment is paramount. You can have the best seat in the world and it will hurt you if it isn't adjusted correctly. I'd say that most seat problems are 60% adjustment. They adjust fore and aft, up and down and tilt (nose down, nose up). Start with level. Lots of good YouTube videos on bike fitting. If you ride much distance at all, it is very important to not be working against your body.