1. If you cannot advance out of bronze 1 you have a very difficult time building your Great Hall.
2. If you cannot build your Great Hall you cannot advance in Arena, above Brutal in Campain or above mid level in dungons.
My teams have all 5 and 6 star L-16 gear. I cannot gain more 6 star gear without advanceing. I HAVE fully upgraded all of my scroll attributes by getting the scrolls through Gems. Speaking of which, is the ONLY way to refresh often enough to get a team or two I can beat in Bronze 1 or 2. When you need to spend 50 gems to win one or two Great Hall medallions it seems a bit of a drag.
When I first started playing this game I felt it would be an interesting change from Might and Magic X, World of Warships, or Guild Wars, but I am finding mtself trying less and less to advance. Yes I still go into Arena for Daily and Clan quests but rather than spend megga amounts of gems I simply lose and stay at the bottom of Bronze 1.