I think the current battling proficiencies and ranks were really well done! It makes a pet that one has stuck with for a long time that much more special! ^^

One suggestion would be to implement this for missions/quests/etc, especially if there are special lost grove tasks.

Basically, if a pet does the same type of mission, they get a "mission proficiency" like the battling proficiencies. As they gain in proficiency, they get better at doing that mission/task...

This would increase the connection to long-term pets, and make the non-battling parts of sylestia more interesting/valuable.