The heated seats are by far the best "extra" you can have. The paddle shift is bad. The paddles should be fixed to the column otherwise you have to look at it to decide which is up and which is down. Not a problem on a racing car as the wheel doesn't turn far enough so one hand does up and the other does down, not so in a Smart car. They really do not like going into first when you meant third.
I don't know what car you ahve but on the 450 (and I think the 451) the controls were analogue so different resistances for different function all down the same wires. This is a really stupid idea because as the vehicle ages and connections get less than perfect the switches change function.
You could try unplugging stuff and re-plugging it back in. I would disconnect the battery first or you will get a bucket load of fault codes.
