Egg laying, which could come with a new survival type game mode where you are assigned into a random nest as an egg and have to grow to earn points which you can spend on perpetual micro boosts for your character.

A perma death mode to tie in with this, along with quests which encourage more ecology accurate activity, e.g: - herbivores get a quest to migrate to a new zone where food is more abundant - Carnivores do carnivore specific gathering like clams, ants, fish etc - Build a nest - Lay an egg

doing particular things to increase a base stat with diminishing returns with a permanent character benefit, e.g covering a lot of distance affects fatty tissue, musclature build up. Same goes for types of food eaten.

Scent for tracking down specific things in game would really help new players

Basically the idea to create gameplay where people are encouraged to fight with an actual reason other than just because other dino bad :P

Just my thoughts on a few avenues to explore perhaps