I personally would like to see a free shard to Crystal feature and maybe have the Crystal to powder one the paid service.
Since the Crystal to Powder conversion is the longest it should not be free however the Shard to Crystal is the 1 hour convert time and it's not that big of a deal to allow it to be a quick convert/batch convert.
The other thing is they to me created a bit of an issue with Shards... You can amass 10-16 a day (depending on your VP) and being maxed I feel most players are going for that one option in the Daily Reward and Daily VP boat..
For me I get 12 a day, that's 84 shards a week, 336 shards a month not to mention stones from the game acquired by raids/events.
Right now I'm looking at my Sculptor and the poor fella can't keep up.
244 Life shards, 230 Ice shards, 877 Magma Shards, 552 Dark Shards