That’s why I love apato. I use it ALL the time in tournaments as a meat shield, although I’ve kept mine all at lvl 20, so up against many tournament carnivores it does often not have enough health to take 2 hits… but it never can get 1-hit KO’d so it still does the trick for me to get reserves off my first dino (particularly with the current AI that often takes so long to attack on the first dino) and at lvl 20 its CD is only 8 hours so I still get to use it a couple times a day. My apato followed by an amphi and carnivore very rarely loses. There also as you said isn’t any other really high health herbivore in the game, only the monostego approaches it, and those can take a bit of time to get a nice bench of.
But it certainly can change depending on your personal battle strategy and where your dino levels are. As you start getting leveled up to where CDs are a concern, then I would agree that the dinos with the shortest ones become very desirable. I’ve focused on a very deep bench of tournament level Jurassics, and rarely is CD an issue, particularly if I can find time to play several times during the day.
But I also am focusing on which VIPs I need the most to fill in where I have the biggest weaknesses on my bench in order to progress higher. I personally don’t tend to buy 20K packs, focusing instead on taking the 11K trade offers in the harbor when they show up. Prestosuchus and Eolambia are ones that I have picked up whenever possible as amphis and herbivores (esp. a glass cannon of the latter) are ones I am looking to get more of in order to get to where I can make my Indoraptors.