Linked cells for brown (and pink) powers
Pink powers trigger more often (every time instead of once per round, or double strength etc.)
First slot can't get anything without paying (no more than two slots! Preferably no more than one!) - this is to balance the above against other boards
Different egg cost progression, also have it vary based on number of birds in column.
Schizo board: Action type changes each column (including bird plays - be careful!) Maybe keep basic play action; it's a wild action that does the worst of everything (have to pay to cycle resources), playing birds costs +1 wild food, you pick any one each time you activate it.
Banner board: Start with 6 brown/5 white/2 pink/1 yellow/1 blue banner, place them on the first empty slot in each row, can only play bird there when someone else plays that power type in that slot, then immediately place new banner.

Base board (reference):
Cycling (&): card->food, food->egg, egg->card
Play a bird: 0/1/1/2/2 eggs
Gain food: 1/1&/2/2&/3/3&
Lay eggs: 2/2&/3/3&/4/4&
Draw birds: 1/1&/2/2&/3/3&

Oceanic board (reference):
Cycling (&): card->food, card/food->egg, egg/nectar->card. Resets (*): food->feeder, food->tray
Supports nectar
Play a bird: 0/1/1/2/2 eggs
Gain food: 1&/*2/2&/*2&/3&/4
Lay eggs: 1&/2/2&/2&&/3&/4
Draw birds: 1&/*2/2&/*2&/3&/4

Linker board:
Cycling (&): card->food, food->egg, egg->card. Resets (*): egg->feeder||tray.
Links (!): Activating a power here->you may pay 1 food/egg/card to activate brown power in linked slot (same column).
Super links (!!): Activating a power here->you may activate brown power in linked slot(s) (same column).
Play a bird: 0/0/1/2/4 eggs
Gain food: 0&!/*1/1&!/*2/2&&!!/3&
Lay eggs: 1!/2/2&/3&!!/4&!!/5
Draw birds: *1/1&/2!/*2&!!/2&&!!/4

Pinker board:

Specialist board:
Cycling (&): food->egg/card, egg->food/card, card->food/egg.
Cycling (*): food/card->egg
Play a bird: -1+B/0+B/0+B/1+B/1+B eggs (B=2*birds already in column.)
Gain food: 1/2&/3&/4&/5&/6&
Lay eggs: 0*/1&/2&/3&/5&/7&
Draw birds: 1/2/2&/3&/4&/5&

Schizo board:
Cycling (&): egg/card->food, food/card->egg, food/egg->card (depends on action type, not row)
Cycling (*): card->food, egg->food
Playing birds has standard egg cost (0/1/1/2/2)
Supports nectar
Grant action: Play bird (+1 wild food) OR 2*cycling (food->egg->card->food)
Row 1: 1 food/1 card&/play bird(-1 food)/3 eggs/3 food&/4 cards**
Row 2: Play bird/2 eggs&/2 food/3 cards&/4 eggs/play bird (-1 food and egg)
Row 3: 1 card/2 food&/3 eggs&/play bird (-1 egg)/3 cards/5 eggs**

Banner board: