Mark, I use terms here that may seem to mean the same thing in practice, but for theoretical explanation (understanding the design) they must be used in their strict sense. Damping (or dampening) and amplitude reduction may bring to the same practical result of indiscernible movement of the mirror, but they work in very different ways and how we go about designing a spider is how much of either we will use in getting to the goal.
Using wire in stretching mode is not really dampening the oscillation, it is reducing the amplitude, while it may not have been damped at all. For example, tightening the guitar string does not dampen it.
The only case when stretching could provide any damping is if the wire would be under so much tension that metal surpasses it's elastic deformation capability and starts entering into plastic deformation zone and this is not the case here. That is the case in guitars (wire sag after some playing), but even then the damping is insignificant.
If there really is any damping here, not just amplitude reduction, it comes from other than using wire in stretching mode.
An easy experiment in frictional damping would be if you cross two wires on the guitar, and see how much tone sustain you get then. The amount of movement is almost irrelevant. Pick them as softly as you possibly can (to avoid buzz) and they will still not sustain the tone.
I'm not going to calculate the difference now in actual stretching force of the wires in your three examples, but I can say with confidence that their angles are not different enough to provide significant difference in the force that stretch the wire under movement of sec holder.
Anyway, even if crossing the wires does not allow for sufficient dampening and even if the angles of "attack" are not significantly greater, then something else there either dampens the vibration, or if not that, it reduces it's amplitude significantly.
I think that what you have gradually done in showing the three examples in the drawing is the displacement of leverage point further and further away from the center of mass, very significantly increasing the arm length that opposes the momentum of hung mass (with practically the same stretching force), plus, introduced certain dampening from crossed wires.
Whether I'm not fully right on this or not, your design is excellent, nonetheless.
The changes that I would do is increasing the damping proper, by passing the wires (at sec. holder) through some hard rubber or soft plastic grommets and possibly rearrange the wire angles and attach points to try to avoid crossing while maintaining the momentum arm length to center of mass...