What we'd considered as a suitable solution (which won't be implemented in any 1.x code, but rather for 2.x code) was to allow any one specific administrator to be set as a "head" admin.
This administrator can not be removed or deleted by any other administrators, and his position can only be reliquished - not taken away. i.e. the head admin can either remove his head admin status (leaving no one as head admin - anyone could then take it over) or assign someone else as the head administrator.
The reason we originally removed anything special about the 'admin' user is because many of the people originally working on this project - Jeff and myself include - felt it was ridiculous that this unimportant username should be allocated special rights. The people I am talking about did not use the admin user for administrative duties, they simply used their own user.
In addition to this - we're not going to make anything special about the "first admin" as all of the Y1G way of ensuring security in this method was too rigid.
Our method is far more flexible - and while yes, it allows you to shoot yourself in the foot, exercise a bit of intelligence, and either remove administrative rights from someone if you anticipate a power-struggle, or backup so you can restore your user if something does happen
