A takedown that does not result in control should be scored as a single landed punch would be, nothing more. If a fighter is controlled on the ground after being taken down, it should be worth more due to controlling the opponent.
Defending a takedown should not count as a point any more than defending a strike, as has been mentioned in this thread. Scoring in MMA is inherently offensive, so you don't score for offense that did not happen. It is a level playing field.
All that said, I agree with those that think too much emphasis is placed on offensive grappling. It seems better now than it used to be, but the bias is still there.