Here are some reasons I like the tunnel shape over the teepee

A tunnel shape makes better use of the tarp or tent fabric for head and shoulder space than the teepee.

When using inside heat the warm air is closer in a tunnel shape,the teepee peak traps hot air that does not radiate down on the bodies in the tent.

The chimney does not have to be as long with a tunnel shape.

It is better if the stove jack in the center of the tent is as flat as possibe.
The tunnel shape is just as good or better in wind than the teepee