Thanks for all these comments, once again.
@Sovereign: Well, Shorty managed to survive and also lead a bunch of smaller longnecks in the mysterious beyond, so...
But yeah, sometimes the values in the game might not make too much sense, but a good balance is more important that absolute accuracy. I try to make it as good as I can though.
Also, once every card is finished, I will check them all and adjust the values if I have to. I already do that with every new card, but still, just to make sure it really does work.
Also, there's something I gotta say (wanted to mention it earlier but I kept forgetting xD):
There are still two more characters needed for this set, and you guys can give me some suggestions. 
(Just don't be disappointed if I don't pick yours when I get more than two.)
To avoid suggestions that already exist, here's the full list of characters so far (already finished cards have a ✓ behind them).
Littlefoot ✓
Ducky ✓
Cera ✓
Spike ✓
Petrie ✓
Ruby ✓
Chomper ✓
Sharptooth (original movie) ✓
Littlefoot's Mother ✓
Littlefoots Grandparents (on one card together)
Ali ✓
Topsy ✓
Bron ✓
Shorty ✓
Pterano ✓
Mo ✓
Redclaw
Screech/Thud (on one card together)
Doc ✓
Dil/Ichy (one card)
Ozzy/Strut (one card) ✓
Ruby's Parents (one card)
Rinkus/Sierra (one card) ✓
Chomper's Parents (one card)
Rainbowfaces
Yellowbellies
I will also update the character list in the starting post with the ticks so you guys can see what's still missing.
So yeah, that was enough blabbering, keep the suggestions coming.

And here's the last card I finished:
