I'll address WF, as I think it's one of the keys to winning quickly and I almost always take gold there. Since the human player gets to propose in the 1st WC about 70% of the time (this is just a guess based on my experience) I almost always propose WF 1st go-round. I almost never propose IG as; 1. I rarely have enough CS allies at that point in the game because I don't prioritize CS, 2. It's late enough that another civ will be up to 15-20 cities by then, and 3. It usually comes at a time when I'd have to break away from focus on something else.
That said, here are my tips for WF, with the assumption that it is proposed in the first WC and goes off around t160-180.
1. Make sure you have Workshops up in all cities AND have IronWorks. This means no late expos unless you have a lot of gold to buy Workshop. I usually time it to complete IronWorks right at the turn WF starts (since I'm usually building PT right around this time).
2. Turn all TR's internal within 30 turns of WF. I sometimes will have a Caravan sleep for 10 turns while waiting for a Workshop to complete so I can send hammers.
3. Build Artist's Guild immediately after WF is proposed. This gives you time to get 1 GA spawned and you want to pop him for the WF. The hammer difference usually takes me from somewhere around 130 to 160+.
4. Get your workers positioned to start chopping forest 2 turns before WF starts. With 4 city/4 worker start, you can average around 120-140 extra hammers towards WF.
5. As mentioned earlier, make sure AI's are at war if you can.
Dirty tricks:
1. Steal workers from a runaway civ. AI often will stop what they are doing and switch to worker production to replace the lost laborer.
2. Send a GG to steal a strong neighbor's production tiles.
There's probably more but I've gotta get back to turning the world Byzantium purple and designing the Inca map from hades.