I did all areas before attempting to visit Stormfist for the 1st time - but I did this to have an easy walk with a high level. On my 1st round I was in my 20es and had a bit of a trouble with the enemies there.
Another reason: the enemies in the Rivertown map had a rather low level, so after I left Stormfist on my 1st round, I rarely got XP (game balance) - therefore I switched the order in my later games.
Kiya