Use your murmuring obols to roll for legendaries at the purveyor of curiosities. The rolls can be disappointing but legendaries come more often than you think. There's a limit to the # of obols you can carry (you'll hit this fast if you do a lot of world events), so use them!

I'm leveling a sorc now as a casual player on world tier 2. There's a lot of versatility on leveling builds. Change things up often and experiment. I found a legendary that put frost nova on 2 charges instead of 1 and it's been a blast teleporting into a group, frost nova, and ice shard machine gunning down everyone. Before that I played around with lightning builds and they were pretty fun too.