a big difference between pets and materials like steel is that you can farm up a fuckload of steel and stockpile it, making it available when needed to regear quickly and go fight again. you might even get some from your dead enemies and make use of it immediately in battle whereas pets dont really have that option, unless you want to do some mid-fight ritualism.
what if you could spend a resource like clade to level a pet up directly? sure you'd have to go get another pet but if you could spend excess clade xp (not enough to de-level your clade but any you have in your current level, which could be quite a bit for those at 20 clade) to bring it up to a viable combat level. it shouldn't be instant so you cant just spam them but over the course of 10-20 mins be able to take a pet from the 10-20 level to 125 would be awesome.
farming clade may not be particularly exciting but its a lot more engaging than looking at your pet growling at some npc it cant get to for 4 hours. maybe make the rate you can feed xp to your pet tied to animal care or something so you have to spec into it for it to be really fast. i dont know what the conversion rate between clade xp and pet xp should be, perhaps it should vary by creature type even, but it would make levelling pets a lot less tedious