I pretty much agree, with some minor additions.

2.  seed:  new traits or developments will only increase price if they increase value.  A corn which is immune to drought would be quite valuable.  A soybean which is immune to damage from terradactyls...well, not so much. 

6.  crop insurance prices are the result of a formula.  They can be predicted relative to the value insured and the volatility of the underlying commodity.  

8.  cash rents are the residual in the system.  As long as the only use for the land it ag, the rent will adjust to the value of the production above costs to produce it, including profit.  On the other side, land values and rents will adjust to keep the return to the investor in line with other opportunities.