Include as requirement to have certain amount of ranger levels, to discourage players trying to bypass the abilities nerf on totems by doing Ranger 3
Get a totem Continue as Druid 27.I may suggest to require 7 or 9 ranger levels.
I don't know where the Totemic npc is, or how easy or hard it is to find him and get a totem...
But I also suggest adding a mini-quest in order so he could win the totem he wants.
On a RP side note, the requirement of certain level may represent the knowledge of the woods and wilds that the ranger needs in order to get attuned with the animal totemic spirit... Also will give some excitement to have the goal to reach certain point to get access to that, instead be calling from zero the wanted pet.
The ranger can continue RPing he is growing a bound with certain animal, but only when he proved to be good enough for the animal, he will attend the call of the ranger.
The mini-quest may serve to give to the Animal totemic spirit the last proof about the Ranger deserves to get the totem bound.