Sounds like you've got the dilithium mining down to a science. What rate are you trading it for or are you just holding it for now?
I'm holding off for now. I'd like to see it drop to around 200 before I buy and I've got plenty more mining to do before I need to convert it anyway (I'd be tempted to spend if I converted it now).
I did discover last night that you can complete the Kerret mission in around 5 mins if you hop instances. That's a potential return of 172380 dilithium per hour! (but would get really boring, really quickly.