In MarioBros1 one went from being SuperMario/FireMario to being a small Mario to being a dead on the next enemy touch. Lives where limited, there where no continues. MarioAllStars later added the ability to restart from a given World.

In MarioBros3 one lost only one ability at a time, so FireMario/RacoonMario → SuperMario → SmallMario → dead. SuperMarioWorld went the same as MarioBros3 but provided an additional extra-slot, that could host one extra and release it on request, thus restoring the abilities. Continues where provided per World, reset points in the world itself where provided by doors, that stayed open even after a continue. Reset points in the levels where not provided, since the levels where relativly short this wasn't a problem.

Yoshis Island used a completly different concept, instead of having special abilites, Yoshis stays pretty much the same all the time (some items can allow Yoshi to spit fire and such, but these are eaten and lost after a short time, there are no permanent extras). On enemy contact BabyMario is released from Yoshi and floats around, he can be catched again, so Yoshi has pretty much unlimited energie if one manages to catch BabyMario in time. Time counts down from max. 30 → to 0, up to 10 energie points are automatically refreshed, the rest needs the collection of items. Progress was saved per level, going forward and backward to older levels is possible.

Mario64 and MarioSunshine used the concept of energie. In Mario64 energie is easily recovered by simply jumping into water. In MarioSunshine energie is recovered by collecting coins(?). No reset points in normal levels, since levels where split in small puzzles that needs to be solved. The jump'n run levels had a reset point at half of the level.

Falling into a hole in the ground leads to death in all Marios.

The trend is after all to make dieing less fatal, loss of energy is easily recovered in most games, but requires a bit of work. Reset points are provided in addition. So the frustration is keep rather low. Progress is often saved per level now instead of per world, thus not forcing you to replay levels again and again. Lives are of not much use since Yoshis Island, they only limited the amount of times one can use a reset point in the level itself, world wise they have no effect.

So how should dieing in SuperTux work? Keeping frustration low and the reset point frequent should be a goal, however it should not be made too easy (ie not providing a quick-save in the level itself). Saving on the worldmap should happen on a per level basis, not per world. Saving should be automatic, replaying levels should be possible. Reset points in the level should be provided, given that the levels are long enough. Enemy contact should cause the current extra to be lost.