Sounds like you just dont like the game. It is still a beta version, which would explain the energy bugs. These things should be corrected as the game is further developed.
The prices of different seeds are fine. The ones, like Mystic, that dont sell for much more than they cost, are meant to be processed into other items, not just sold by themselves.
Dirt costs more to prepare in the later areas because thats how rpg games work. It gets harder and more costly as you advance in level, otherwise it would get really boring, really fast. The same can be said about the time it takes to process herb into other products. It takes more time to make tea than milk, more to make candy than tea, more to make ice cream than candy, and so on.
It can be assumed that when you just sell herb, and not process it into an edible, that it is sold for smoking purposes. The game is about production and sales, not consumption of the product.