This thread makes me roll my eyes so hard. Not because people don't agree on optimal strategies (which is fine, if there was an optimal strategy that everyone agreed on I would say Firaxis made the game wrong), but because they are getting so worked up about it.
I only play multiplayer with other people or hotseat vs myself. When I play against myself I go 8 civs, all random, continents, standard size and game length, with everything else standard. In other words, what the game was balanced for.
As usual, there are different reasons to pick different things. I always go scout first, but I used to always go monument first. I will attempt to explain why.
1.) Monument first
Pros: Early culture, which means quick policies
Cons (other than opportunity cost of course): If I am going Tradition, I might get nothing from the policy that gives free culture buildings. Also takes a while to build
What am I going to get with those policies?
A) Tradition for more culture and faster wonders
B) Liberty for a settler/worker
C) Honor to get culture from barbs (and indirectly xp and gold because its easier to fight and take camps)
If I rush into Tradition with a monument first, I won't have improved territory due to a lack of a worker. This means that the +15% wonder building is roughly 1 hammer...and I shouldnt take the free culture building policy because I will get nothing in my capital (havent had time to research philosophy)
If I rush Liberty I can get either a settler or worker. If I go settler, I can't afford the happiness due to the lack of a worker improving my luxuries, and if I go worker...why didn't I just hard build one? I suppose you could, but still pretty weak IMO
If I rush Honor, then I am going to get meager amounts of culture from killing barbs. In order to make this worthwhile, I should now ONLY hunt barb camps, but since I build a monument first I only have my 1 warrior which is still hard to take camps. If you build a warrior second this problem is fixed, but then you have the additional opportunity cost of that...not worth it IMO
So monument seems a bad idea.
2.) Warrior first
Pros: Scout that won't die as easily or can take barb camps.
Cons: Can't scout as well as a scout, also takes longer to build
If I get a warrior, I can either scout or fight barbs with it.
A.) Scouting. Your warrior takes longer to build than a scout, and those few turns truly make a difference. You can't know because you aren't omniscient, so try a hotseat game versus yourself. You will see that you will often grab some ruins 1 or 2 turns before another civ, and vice versa. It hurts! The ruins are great. +20 culture is just as good (if not better) than a monument, upgraded units are wonderful and just as useful as the honor policy VS barbs or a second warrior, maps reveal more ruins, tech is AMAZING, gold can purchase you a worker or monument or a city state friend. The only useless ruin is the barb camp reveal. That is useless because if you wanted to go barb hunting you would 1) not be scouting for ruins and 2) would have taken Honor so you'd find them anyway.
Also the scout moves through rough terrain so much easier than a warrior. And I know how to move my units to get the most scouting possible even with rough terrain. A scout is still better. And if that scout gets upgraded to an archer, then you have a kiting archer of awesome. Scouts are especially wonderful for Spain so that they can find the natural wonders earlier than other civs.
B) Fighting barbs. If I want to fight barbs, it is for 5 different reasons.
1) Gold from camps. Which is not worth not having the better scouting (+30 per CS, roughly 80 per ruin that gives gold)
2) Culture from Honor/Aztecs. Still not worth not grabbing a scout and/or going one of the other trees.
3) XP from barbs. Definitely not worth it, are you ever going to trade +30 xp for 20 culture? And you certainly won't get only 1 extra ruin from going scout.
4) Influence with CS. This can and should be done AFTER scouting
5) Just get rid of them. Not necessary since you can kill them with your city. And you can always have your warrior stay home and defend your worker if it really comes to that (which it never should, the barbs will more often than not attack a CS because they are closer)
They only reason I go warrior first is if I will get all of these (gold, culture, XP, influence, and save my worker) AND I have a special ability that goes well with barb killing. Like Germany (units and gold), Songhai (gold), Ottomans (units and gold), Aztecs (culture), or Greece (influence). You can get money from scouts (and more of it), culture from scouts, techs from scouts, and upgraded units. Unless you can kill 4 birds with 1 stone from barb hunting, it isn't worth it.
3.) Worker first.
You won't have the tech to use your worker well when he comes out. 'Nuff said. You will either need to get a free tech from scouting (much more likely with a scout instead of a worker start), or beeline like a boss to make the worker even worth the hammers let alone the opportunity cost.
4.) Scout first.
As stated above, you get so much from ruins. And although you may not believe me, you will get a lot more ruins for grabbing a scout. Play a game against yourself so you can see whats going on. Go scout for some and not scout for others. Watch the difference. And a lot of ruins spawn in stretches of rough terrain that you wouldnt bother trying to explore with your warrior (which is why you don't know theres ruins that you lose to AI in there). When your scout meets CS first you will cheer, when you get to snipe CS workers out from barbs you will celebrate, and when you get tech, or culture, or kiting archer from ruins you will go crazy.