At the current rate, aethersparks were quickly losing value. This was due to the amount being earned was much higher than the amount being used.
The plan for aethersparkes was for them to be an optional premium currency. The goal was to make sure that players could always progress, but if they wanted to speed up the process, they could. At the rate the economy was going, they would have been meaningless before long.
As with all f2p games, we'll always have avenues for players to spend if they so desire, but it's our goal to make sure that it's never mandatory and always fair.
I hope this adds some clarity :D