India is a VERY BAD IDEA! I played on a Huge map and I let them grow out quite well. When you puppet it increases unhappiness greatly. You may not think annexing is a good idea but when you get so much Culture you don't want to put them into the last trees nothing you can do.
I kept all options viable because I like my things to go to HoF. =)
In the late game yeah it gets very long on a Huge map but it pays in the end.
I might try to cap population on one city tomorrow. One MAJOR problem I did was killing all the Marintine CS's. I wanted their land without thinking their growth gave me more points.
India is by no means a bad idea! Break-even point for city size (India vs. other) is 4 - in any city larger than 4, India wins the hapiness / city size contest. Basically, India means "bigger cities". Indian puppets also cause less unhappiness as they grow - their UA works on puppets as well as settled cities. India is my favourite for mass puppet empires.
Ignoring policies (which just make India's cities even bigger), let's look at the maximum size a civ can grow a city while minimizing unhappiness:
Non-India: You can never (without policies/wonders/luxuries) have a city that causes no net unhapiness. The best you can do is -2 until you account for policies - and policies push it further in Ghandi's favour.
e.g.
Coliseum: Size 3, -2 net happiness
+ Theatre: Size 7, -2 net happiness
+Stadium: Size 12, -2 net happiness
(+ Circus: Size +2)
India:
4 Unhappiness from City, 0.5 unhappiness from population
Coliseum: Size 3, -2.5 net happiness
+Theatre: Size 7, -0.5 net happiness
+Stadium: Size 12, +2 net happiness
(+ Circus: Size +4)
Same 'net' for comparison's sake: Size 16, -2 net
Now let's add in policies & wonders
Summary of modifiers:
Theocracy: -25% from pop
Planned economy: -50% per city
Meritocracy : +0.5 per city
Forbidden Palace: -25% from cities per city
Military caste: +1 per garrison
Freedom: -0.5 per Specialist
Let's look at our old size 12 City with all unhappiness buildings now.
Non-India / India
Base net hapiness : -2 / +2
+ Theocracy: +2 / +4
+ Planned Economy: +3 / +6
+ Meritocracy: +3.5 / +6.5
+ Forbidden Palace: +4 / +7.5
+ Military Caste: +5 / +8.5
+ Freedom: Varies with # of specialists (I'll ignore it for now)
So, what's the largest city each can have when you account for *all* of this, and still have no net unhappiness?
Non-India: 12 + (5/0.75) = 18 2/3 (20 2/3 with Circus)
India: 12 + (8.5/0.375) = 34 2/3 (38 2/3 with Circus)
16-18 extra population PER city! Now, if going for a points game, there is no way that's a bad idea, unless I'm missing something big.
In city-spam India games that you let run till the end, you can run happiness surpluses into the hundreds per turn - population growth can't nearly keep up with the rate you acquire happiness buildings at end game, and it's worth having as many cities as you can for points (you get higher total population with more cities - per city + food modifiers and more specialists only consuming 1 food each instead of 2 => spam is best).
I can understand in a 'real' game that other civs are better, but for an abuse-the-mechanics, score as much as possible type of game, I don't think anyone holds a candle to India.