I don't like the ranger and I have been experimenting with new variants for the weaker features. One feature I don't like is Primeval Awareness, allowing you to expend a spell slot to know if certain creatures are near you, not telling you where they are or even what type of creature it is. My idea is a feature that allows you to change your favored enemies or terrain.
Natural Attunement: At 3rd level, your attunement to the natural world increases. As an action, you can expend a ranger spell slot and choose to either replace one of your favored terrains with a terrain you are currently in or change one of your favored enemies to a creature type or a race of humanoid you have interacted with in the last 30 minutes. This change lasts for 12 hours. If you change your favored enemy, you do not change the language you gained from it.
Basically allows a lot more flexibility for the ranger, giving them an exploration feature that makes them basically a fantastic tracker in any terrain or for tracking any creature. There is a few limitations (only 12 hours, one race of humanoid), but it is extremely flexible.