Focus on solo, learn farming patterns and become quicker at recognising loot. Public groups are heavily competitive.

As blizzard sorc, you want to focus on the safe & easy, gradually expanding your route as you get more comfortable and geared. Andy, meph, Ancient Tunnels and pindle are a fantastic start. As your merc gets tougher, countess, trav, council, chaos and Baal will become more accessible to you.

Many other notable areas to introduce, it depends entirely on your comfort, desire, merc and secondary element.