Ser & Estar

Ser and Estar are two ways of saying ´to be´ in the Spanish language.

Now, this is a raft of information on the internet on this subject, so I will not repeat it here - however, these are my thoughts on the subject:

Ser:  Is a descriptive of a permanent characteristic.  e.g Soy de Escocia (I am Scottish)
Estar: A permanent, constantly changing descriptive of a characteristic. e.g Estoy esperando (I am waiting).

Estoy esperando, is a temporary state for me at that time, when I was waiting.  I was at that time in the process of waiting.

Obviously, as is the case in English people can qualify to be śer' and éstar´ - for example, I could be quiet.

Soy callado.  This would be permanent, I am a quiet person.
or
Estoy callado.  This is temporary, I am at that moment in time quiet.

So, people are constantly changing evolving in states of estar.   A man could be:

Es borracho.  A drunk, by a description of his permanent state.  Or Está borracho - drunk at that moment in time.

Curiously - está muerto.  He is dead.  Es muerto, surely?  No - because death - while permanent, is a change to his permanent state, when he was alive - curious, as I said.

However, finally - looking at day to day use of the language.  Estoy viejo, could mean I feel old - Estoy joven estar aqui, the opposite.  For example, I am young, or I feel young to be in this position.
  
So, I think I understand to some extent - the basics of the ser v estar concept.  Spanish, perhaps has an extra level of sophistication to English in this respect?