1) I like to change the PIN so if I am doing a split transaction at Walmart, I don't have the fumble to figure out the last 4 of each card. Makes it seamless to swipe and enter the same pin every swipe.

2) Doing on the phone is possible but incredibly tedious.

3) Mygiftcard Visa site rep reported that the website functionality (including checking balances/transactions) has indeed been disabled. It is "supposed to" return at some unspecified future date.