@Aaronius: I saw a post recently in the Strategy forums that details how military strengths are calculated, and naval units count for next to nothing -- should explain most of the discrepancy.
I'm at turn 157 now, met Suleiman early and sold him gems early. Focused on getting GLib up, missed HG and Oracle but didn't focus on them very narrowly. After GLib (used to pop Sailing), switched London to food focus until it got to size 6 and delayed National College awhile to get some Triremes out and building up experience on barbarians. Have met several other powers and spread the gold around -- made friends with Germany, China and Egypt because they were friendly to begin with and friendly with each other, so far that's being a mutually reinforcing dynamic. Have refused other friendship proposals. Suleiman was never friendly, and recently attacked with warriors and archers (which I quickly wiped out with an archer and my triremes). Am now pushing to take Edirne and its iron supply before moving down to Istanbul. I've got a solid fleet of 5 or 6 triremes at this point, most of them with two promotions (accelerating now that they're shooting at Turkish cities). Initial warrior upgraded to spear on a ruin, have upgraded it to amphibious for city assaults from the water. Built an archer and a swordsman for land infantry so far, but have mostly focused on naval production.
Settled London in place --> build order Monument, Worker, GL, trireme. Bought a granary while GL was building. Waited to build any scouts until Optics was popped, so early production was spent on culture/growth/wonder priorities. Settled City # 2 at the isthmus NE of the ivory to allow pass-through, which is looking like a good call now since Istanbul is facing away from me and the coastlines are pretty winding on the north side. Bought library there almost immediately after founding. Have popped city #3 on the island to the west for the sugar and wheat, bought library there to keep NC construction rolling. After NC finished, started building HS (fingers crossed).
Am avoiding RAs for the moment --> I feel like I'd rather use the cash to build up infrastructure in my cities and keep them clicking along as quickly as possible. Plus, that leaves me more latitude with respect to foreign policy.
Overall, I'm happy with how the game has been going so far --> HG would have been nice, but London's big enough right now to get the important stuff done in a timely fashion and in the absence of boosted growth I've had enough excess happiness to allow #2 and #3 cities to grow quickly. Looking forward to the rest of the Ottoman campaign (Suleiman hasn't shown any sign of effective resistance and already offered an even peace before I even approached Edirne), then will reevaluate broader strategy re: other AIs when my iron supply is secure and I've grabbed Edirne and Istanbul.
to answer the OP questions:
initial priorities:
* take advantage of the starting location to get GLib and a large population up in London
* get initial luxuries sold to expedite London's development
* get a trireme fleet in the water and gaining experience ASAP
Social policies:
1) Tradition opener 2) Aristocracy 3) Liberty 4) Collective Rule 5) Republic (had 2 workers, one built and one bought, for 2 cities at that point) 6) free worker (for the third city)
chosen to boost London border expansion and expedite GLib construction as much as possible, then get a second city down to cut off Turkish approach and secure ivory and isthmus pass-through for future strategic purposes
Tech path:
1) Pottery, popped Animal Husbandry from a hut, 2) Writing, 3) Mining, 4) Sailing, popped Optics with GL, 5) Archery, 6) The Wheel, 7) Mathematics
Wonders prioritized:
GLib (got), HG (missed), Oracle (took a late attempt at it because I delayed Philosophy, missed it), HS (took my time getting to the tech, am building it now, fingers crossed)
So far, additional city states haven't affected much --> only encountered one early and didn't want to take out the barb encampments since they are good sources of experience for triremes