Being an owner of 3 collared mounts, and likely dozens of others, I have become acutely aware of how useless non-invincible artie pets (1250cr) can be, due to the fact that they are so easily killed, and take so damn long to respawn.
Just to throw some numbers out there, the mount with the highest HP takes the following amount of damage/HP to kill. It should be noted that most mounts have either less, or significantly less HP. (the ranges provided are unartied/artied)
Smite: 14-18% (~10-13 seconds to kill).
Gut/Incantation 16-20% (~15 seconds to kill).
DSL up to approx 20-25% (~8-10 seconds to kill, dodging excluded (not an issue with artie weapons))
[Haven't tested with Jhui or equivalent arties)
There's also the issue of mounts being caught outside your room, in which case they're basically toast, rendering your 250cr pet and 291cr Riding ability essentially gone, with no way to get it back for 18 hours. (lets rule out the practice of carrying around 50 mules in your inventory, for a slew of reasons).
Also, mounts can essentially be "slow prepped" but damaging them/running, preventing the only counter to mount bashing (10-ish seconds of getting attacked by the mounts owner)
On the one hand, the primary reason for their low HP and damage mitigation (none?) is for combat balance purposes, however that logic is somewhat moot considering that invincible pet mounts exist (the only "balancing" feature of them is that they cost a fortune).
The following solutions are a few ideas, any of which I think would help close the massive practicality / balance issue between artefact and non-artefact mounts.
1) Implement some way of healing mounts, that uses balance. Perhaps a crafted item that can be fed/applied to a mount that heals it by perhaps 10-15% health, at a 3 second balance cost to use. This would not out-heal any class' ability to DPS them out, but would create the ability to flee and slowly heal your mount up in order to prevent its otherwise entirely unpreventable death.
2) Implement a level 2 collar, or separate collar-like artefact that can be attached to mounts, that increases their max health / rate of healing, significantly.
3) Implement forged and/or artefact mount armor, that can provide fixed % damage mitigation for mounts. Higher levels for higher mount types.
4) Implement a (Lupus-related?) denizen that can be used to resummon collared mounts, outside of combat, for a cost. Wouldn't help in the arena, or during combat, so not the best solution.
5) Add an ability to Riding that allows users to increase a mount's health, hps, or mitigation for a fixed period of time, or perhaps with a significant endurance or WP drain.
6) A rune, or other such temporary buff, that can be cast on mounts to temporarily boost their mitigation or max health.
Probably several other ways to address this as well. Open to thoughts - will submit classlead based on feedback.
(Please note that combat balance was taken into consideration for these ideas, with an emphasis on keeping artie pets 'better' than anything else. The goal is to create a way to use mounts without having to simply accept the fact that they're going to die in the first 10 seconds of every fight, completely removing your ability to use an entire Skillset and very expensive pet).