If an ejected player wishes to explain himself, listen, don't argue. Accept apologies gracefully. If a team pleads with you not to file a report, let them know that you have no choice and can yourself be disciplined if you don't file. You can appear sympathetic. Just as one should avoid ejections, one should avoid formal cautions that might prematurely lead to ejection.
Cautions come in various levels of specificity.
If a player commits an offense covered by the caution, they must be ejected. So, you don't want to give a general caution to both teams for anyone throwing a punch this backs you into a corner. Keep cautions specific and limit the number of players cautioned. Thus when you sin-bin a player, you must deliver the formal caution, preferably in front of both captains, so that there will be no confusion as to what constitutes a repeat offense. When you formally caution a player, take a moment to record the time, the reason, and the number of the player.