To start off, I don't like the dilithium changes with S7, but I'm not going to speculate about the motivations.
A large part of my game play involved buying and selling DOFF's, and I'm uncertain of how that will play out in the future. I'm picturing an eventual glut of common and uncommon officers on the exchange due to them not being worth grinding or dismissing. They will have no real value in game, and no one will really want them for anything other than starbases.
So I have to ask why the lower tiers of DOFF grinding saw a 5000% price increase while the very rare tier saw only a 2000% increase?
5 commons --> 1 uncommon = 500 dilithium (5000% of original cost of 10 dilithium)
5 uncommons --> 1 rare = 2500 dilithium (5000% of original cost of 50 dilithium)
5 rare --> 1 very rare = 5000 dilithium (2000% of original cost of 250 dilithium)
I think it's because someone realized that a 12500 dilithium cost (5000% increase) for the very rare tier would be absolutely unpalatable for most players. I just don't understand why that wasn't recognized for the lower tiers as well. Why not keep the pricing consistent with each tier being 20% of the cost of the next tier? The pricing should be 200, 1000, 5000 not 500, 2500, 5000. It would at least making grinding at the lower tiers somewhat more palatable and keep the pricing consistent.
At the current prices, I don't think I'll ever grind a DOFF again. My dilithium is too valuable.