Im landing in airport 19th december I'm thinking about using the train to casa voyajers and take a cab to hotel amoud but is there a better way such as bus or sth else.

No . the cheap way to do it is to take the train to casa voyageur than the smal cab to the hotel,
How much is taxi from Casa Voyageur to Hotel Amoud these days?
Hi,
Have a look in the top questions box on the right of the page.
The smal cab in Casablanca has meter, and i dont think will go over 30DH (Morocain money) but sometime it's hard to find one or they will try to charge you more than that . Good Luck .
Agree with reply # 7, The price always given depends on the accounter how many miles you take from place to another, but although they make some extra charge depends on the arrival time and the distances try to negotiate the price, as Moroccans Do wherever they go, to get the best deal.