This is a game meant for premium players. If card trading is allowed, they won't even pay that much. Like a Gashapon machine, premium players will just draw and draw till they can HP their cards. They are willing to pay to be that strong, thousands of dollars are spent by the very top ranked players. There is no way a non-paying player has the right to complain about the difference in strength in the system.
Card trading will give rise to low level people having super strong cards and many "empty" accounts just to store cards, etc. It will make the system even more complicated and tougher to control.
Also, I do not know what you mean by trolls. I really need an explanation on how a browser game like KHx can have trolls.
Don't forget that majority of the players are from the beta period. Non-paying players like me take a lot of time and luck to be sufficiently strong. It took me 5 months to have a full HP SR+ assist deck and make more than 100million lux per week, and right now I just have my 4th HP SR+ attack card in my deck and can earn at least 250million lux per week.
I have read your posts in other threads and they are very selfish. The amount of gameplay and access provided to free players is tremendous. We draw the cards at the same rate as the premium players. When you get strong enough and join a good A class team, your team can provide you with so many mission rewards. The community has been very friendly and good sporting all this time, there are some opposing teams that created their own threads just to chat with each other during that one day.
Please be thankful to the things we are able to enjoy, eg. we are already having Combo Plus and more Orihalcons as mission rewards. There is no right to complain about anything unless you are paying a lot and are still not strong, and even then its luck. Don't forget that games like KHx (your tv shows as well) are meant to generate profits for the respective organizations. Businesses can resort to all sort of dirty methods to earn money (eg. look at the amount of Disney Infinity figures).