Nolan's post in Skill balance was marked as the answer
Devs never make adjustments to skills in order to make them unbalanced (keep in mind that there are hundreds of them + relics that interact with such).
It's not an easy job to keep them balanced all the time, that's why devs need to get as much data as they can and use the statistics for future rebalances.
Nolan's post in Question regarding mailbox was marked as the answer
There isn't a limit of how long you can keep those mails with attached items (rewards/gifts/achievments), but the empty ones will be deleted after 12 hours.
Update 7.1: Previously you could to accidentally delete a letter that holds any attach, but now no such message will be lost until you do not put your gifts or gold in the bag. Information letters without attachments you can delete yourself. Or they will be automatically deleted from your mailbox 12 hours after receiving the letter.
Nolan's post in Can you get banned if you accept things from a hacker? was marked as the answer
The only way it may happen is if you accept suspicious items or gold from someone in the game and this person requests a refund.
It is very likely that both of your accounts will get automatically blocked and you will have to contact the tech support in order to find out what happend.
Therefore, check our refund policy.