Good
Surplus production occurs when too much of a good is produced. Supply then outweighs the demand.
no oak is heavy and costly, in one aspect its harder therefore has greater structual integrity but overall cost and energy required to work with outweighs the bad
the public good outweighs individual civil liberties.
Excess demand occurs when demand outweighs supply. This means there is a shortage of a good.
In Islam the meaning is two Angels sitting respectively on your shoulder. Recording your good and bad deeds. Which ever one outweighs the other wins and you either go to paradise or hellfire
In a good relationship, all parties feel good about each other most of the time. Even in the best of relationships there can be negative emotions, the difference is that in a good relationship, the good far outweighs the bad.
The effects of tanning are definitely that the bad outweighs the good. You could possibly get skin cancer from using a tanning bed, and it's really bad for you.
Yes
The unpaid intrinsic fulfillment far outweighs any proposed negativities.
There is no ranking of the mitzvot.
You gain in the end despite investment
If the feelings are reciprocated, then sure. But be careful, if the relationship doesn't work out, you may lose the friendship. Ask yourself if having a relationship outweighs the friendship.