....I can stomp them on prince though my science victories are sloppy...
Although you wanted general advice I'm going to give advice on science, which in this game is the key to everything, except diplomatic victories.
Growth and specialists(Secularism and/or Korea) are the key. Settle in locations that has a river so each riverside farm will yield +1 food at Civil Service. Try and settle next to the river so you can build the watermill, garden, and hydro plant(s). Your capital is the main source of science so consider sending all internal routes to it(initially). Also allying or befriending maritime CS is never a bad idea.
War
Although war can be very beneficial it is usually costly in terms of science as each city you found/capture adds %5 to your tech costs. Puppets always focus on gold production and not science, unless you annex(which will ad to your policy costs) or send an internal trade route to them.
Wonders
The only early wonder you want is the Oracle, you can get this in an expo on Emperor if Pacal and/or Maria isn't in the game(there's a few other but I forget who). Early wonder-whoring means you are focusing on production and not growth. In saying that Temple of Artemis is a nice wonder to snag but it will usually go early.
Wander your Settler
Turn off barbarians in the meantime and wander your starting settler. Usually you get an OK start but there might be an excellent location a few tiles away.
Civs to Try
Aside from the obvious science civs like Korea/Babylon
Spain: you don't need to settle a NW, only find it first. That's a free settler or 2.
The Huns: it may seem Attila is about early war but he's about insane production. I once built my SS parts in 4 turns in an excellent Attila's court(would have been less(probably) if I went Order).
Poland: the only civ to guarantee opening Rationalism the turn you enter the Renaissance era.
Polynesia: on a watery map they have the advantage up until someone reaches Astronomy.
If you want ideas on what excellent locations look like have a look at the finishing screenshots of the games in
The Deity Challenge Line-up #20 - Spain - Valentine day Resurrected