I do have one complaint re the basic decks, though. While I realize that being able to edit the decks would defeat the purpose of the trainer challenges, I do think that when you earn a new card for each deck, you should be able to choose which card to give up to make room for the new one.
As it stands now, for instance, there are NO healing items in my blue deck. I'm guessing this is because ,once I earned the stadium card that heals 30 points every turn, the devs thought potions & all were unnecessary. But, if that stadium card doesn't come up early on, or is stuck in your prizes, you can lose really quickly.
So if any devs read these comments, please consider allowing players to choose which card they want to sacrifice to make room for the prize cards you win in the challenges.
Also, more goals (with rewards) would be great. Like a 5 coin prize for using all 4 decks on the same trainer. Also, why stop the deck use rewards so soon? How about a reward for winning with the same deck 25 times, or 50 times? Finally, unless I'm missing something, it seems that once you complete a challenge level (gold, for example) using the "easy" mode, there's no incentive to try again using the medium or hard modes... but it seems like there should be.
Hopefully someone at "Pokémon Central " will read this and consider adding some additional reward levels to the trainer challenges, as well as the option to choose which card you are willing to lose to make room for the existing rewards. I'll be keeping my fingers crossed, lol.