Have angels existed for eons, and thus have both extensive experience and wisdom?

This is very much the case. They were created prior to the existence of the current physical universe, so their experience base and reach are vast indeed. They have followed the new unfolding of life across the universe and have seen firsthand many, many situations of all kinds where organisms were in competition in ways to create difficulty. And to sort out how to reconcile things and be of assistance at times when things became too far out of alignment and divine help was needed or requested. They are quite superb at this and serve all kinds of functions to assist with inspiration, to assist with guidance and support directly and indirectly—including physical interventions in the earth world at times to rescue people in danger, or to make something happen to bring about a change that has been prayed for, or to restore balance as part of healing underway. There can be influence on individuals to help another indirectly. There are many ways the angelics can manipulate things by changing things in the environment and other creatures, to bring relief for a human being pestered or endangered, or to rescue animals at times, who are struggling and suffering in some way and are unable to take care of this on their own. Just like humans endangered by accident or other mishap, animals, too, will suffer and need divine assistance at times to get by. It is the angelics in large measure who see to this, often with the awareness and direction of Creator initiating their answering the call, so to speak. But they do many things at their own discretion, primarily when tasked with a particular duty to provide oversight for a particular individual or situation in the manner of standing guard. And this is true of the guardians in particular, who will stay close to their charge, to be at the ready and assist when needed.