I also support puppets not contributing either Gold or Science to the conquering civ.
Hell, let them keep contributing those to the Civ they were from!
That would be worse.
There needs to be some reward for conquering... since there is a cost
At a Minimum you get
Cost=Military
Benefit= Enemy doesn't get city (outputs or territory)... but enemy no longer pays city costs either
Razing-> No city costs, no city benefits
Raze+Resettle->Normal city costs, Normal city benefits* (this probably needs to be weakened as an option.. by either making Razing harder, or making Annex/Puppet give better benefit-cost ratio)
Annex-> Normal city benefits+costs: +Free Pop, Territory, Buildings, -Short term Unhappiness+Build penalty, Long Term Maintenance.
(I might remove the Maintenance of the Courthouse... perhaps change it so the cost depends on the population of the city as well.)
That would make Annexing > Raze+Resettle most of the time [ you could also increase the # of surviving buildings+population to do that... and nerf Maritimes]
The issue then is Puppets
"Minimal" puppet rebalancing would reintroduce control (still no Wonders/Units allowed)
and give 0 Culture.
What might be Better is to make Puppets the option over Razing.... ie they give (almost) no benefits, and have no costs
So if you want the output of the city
Annex or Raze+Resettle
If you just want to deny the city to the enemy
Puppet (no costs at all... only benefits=production for buildings, or Raze
Puppet would get the benefit compared to Razing that
1. It would be available for Annexing later... and would improve itself in the meantime
2. It would provide control over the territory (major beneft gaining resources, blocking enemies)
3. It would provide defense
The disadvantage of Puppet compared to Razing would be
1. No resettling (but then you compare to annexing)
2. City can be reconquered.
So the Warmonger would attack and get his vast number of puppets, but wouldn't have any benefits from them, until he was willing to take the happiness hit.