(sections removed all my doing)
I imagine that is what runic 2 pet addresses. That pet can tank monsters from what I've seen/heard. Weak is not a word I would use to describe high tier mage pets.
Does your level 4 pet feel underpowered as you reach level 8? Sure does.
Does the level 63 pet feel underpowered when you're at the point of killing relic dropping mobs? Absolutely.
Does the relic pet feel underpowered when you're capable of getting runic 2 pages? Sure.
Maybe you're just ready for a new pet?
I would agree I am ready for a new pet, but I don't have much time to play as of late. So, I can not personally speak of the runic 2 pet strength. Maybe an r2 mage will come in and toss in their opinion. If I remember correctly, the mages I talked to were annoyed when all our pets lost hp across the board. But from what I've seen. r2 mage pets are awesome, and I do want one, and much more powerful than the relic.
I think you may of unfairly chopped up my statement. Most the arguments I remember seeing have to do with how pets improve on
mitigating the dmg, which is to say a lot of times they don't improve on mitigating dmg. Which is difficult when you go through the tiers. An example of this, if you were to plot the base hp of all the earth pets up to relic ( I don't have access to r2, but r2 won't fit properly on the plot) versus the level of the spell you will find it is an exponential curve. y = m(e)^rx. The effects you get from items and loots through the tier, pet heal, pet str, etc. They improve in a linear fashion. So the curve of the pets literally flattens out, until you get an r2. That would begin a higher point, but by the time you get him you have pet health 8 and str 8 most likely. So no more possible improvements, though you get 2 more pet class tomes for cool ww and DB!
Now here is the key: Pets do fine with the mobs as you level up 0-63, because every few levels you get the new pet. But, because the you start to get relic spells at tier 3-6. It is spires where you get access to r2. So, how do mobs in relative exp zones improve in strength. Is it linear or exponential. To me, that's the crutch of the argument. I think it is exponential in fashion, because in my experience my pet does very well, then barely, then very poorly as monster's toughness improves. It's a rapid change. (I could be picking the wrong mobs and as a person I always suffer from a confirmation bias.)
From my understanding, the reason the problem happens is because the mobs are balanced against the tanks and rightly so. As the tanks go up in tier, their mitigation of dmg improves. Pets by their design can't improve their mitigation much. Mages have lightning reflexes and the AA to share it with their pets. Some of the pet silks armor has dmg reduction on it. Companion armor I. These are mechanisms to help with the problem, but maybe not enough. Also, CoP.
One suggestion I had, I don't know if it's practical. Would be if you could some how tie a pet's (any class's pet) mitigation to the hp/mana of the owner. Because that is one way that we gauge tier level. It could come out as a set of companion tomes and it would be in the same vein as the others.