I keep my pets on an extremely short leash and seldom have many problems with them. My attitude about them is that my tamer is the one making the majority of the decisions about what to kill and when to kill, not the pet. The pet is just a weapon.
Most of the tamer characters I use are peace tamers. However, I seldom use the peacemaking skill while hunting. I primarily use it when I need to run the tamer (with or without a trailing pet) through a particularly nasty area or when out marking runes in nasty spots. Once in a while, if no one else is around in the area, I will use it to hold off mobs while I loot a corpse, but doing that is iffy at best. Why? The biggest problems with using area peacing while hunting are (1) when it wears off, the monsters often change targets and their preferred target generally seems to be my tamer, and (2) if other people are hunting in the same area, I feel it's extremely inconsiderate to cause the same monster-switching-target problem for them and/or to drop their dexxer out of war mode.
When my pet is not busy killing something, or if I'm waiting for something big to spawn that I want to honor, it's in follow mode. I have my follow macro set up on two lines: All Stop / All Follow Me. I've also got one "stay" macro for each of two separate named pets, i.e., one macro for "A Stay" and another macro for "B Stay."
For killing stuff, I have my choice of three separate sets of macros: A two-line one that says "All Kill / All Guard Me"; another two-line macro for one named pet (e.g., "A Kill / A Guard Me"); and yet another two-line macro for a different named pet (e.g., "B Kill / B Guard Me").
If I'm hunting stuff that spawns in a crowd, I generally try to pull the stuff I want to kill off to the side a bit to avoid getting overwhelmed. And if something big spawns while in the middle of a fight, I immediately issue a stop/follow command and pet and tamer begin looking for a quieter place, hopefully before the new big spawn takes notice.
If the pet has multiple monsters attacking it, I always try to have in mind the order in which I want them to die (or not). In some cases, it is beneficial to just let the less powerful spawn stay alive to avoid having to constantly keep dealing with new stuff spawning and wondering what it will target. Therefore, I generally have the pet kill the most powerful monster first and then kill the less powerful stuff if I want its loot or we're going to move on to another area. Sometimes the pet takes out the less powerful stuff while it's killing the more powerful monster. That's okay too, but it generally means having to redirect the pet with a new kill/guard command to keep it occupied with killing the most powerful monster in the mess.
I always play with the sound on. It helps tremendously to hear the different sounds your pet makes when it is not in peak form. I also tend to distrust the loyalty rating information and feed pets fairly often regardless of their loyalty rating. I also try to avoid giving multiple follow commands when the pet has gotten stuck on some obstacle and just run back behind and away from it again to help it find the proper way out of whatever has trapped it.
I very very rarely anymore get clobbered by a pet. It was an almost daily occurrence though when I first started playing with a tamer character. What helped tremendously to get out of that mess was to fix my tamer's macros for invizzing, curing, and healing. I set up separate macros for performing these actions on my tamer and for using them on other characters. The ones for use on the tamer character are all three lines long: Spell; WaitForTarget; Target Self. I also make myself use Control-Shift to bring up the bar of whatever I want to have the pet kill and target the bar instead of the body of the monster. When I slip and don't do that, it invariably spells trouble and something dies that shouldn't (e.g., a guildmate that has no hesitation about giving a murder count to teach me a lesson! LOL).
Sorry this is long and hopefully it doesn't sound condescending. Good luck to anyone who's just starting to use pets or just came back and is shaking the rust off an old tamer character.