If going for the big turn, as many caravans as possible is important as its the only source of "+cards" to increase the amount of potential bridges to play in a turn. Shanty Towns could be, but there's probably a need to have Bazaars > bridges for it to be effective (rather have it as a lab then a non-drawing village of course).
The hard thing to adjust for is when to unleash this amount because once it buys 3-4 provinces, it really struggles to gain any other provinces. Thus its important to unleash only when it end the game. Although if you buy a cellar, it may be able to alleviate buying 3, and then 2 or something of that sort.
Also, early $5 (T3/T4) probably needs to be treasury. Only because $3 here is SO bad (one shanty isn't so bad, as long as you priortize bazzars = bridges +1 and have cellars, but that's a couple ifs).
The bigger the turn your building to, ie. trying to finish the game. Markets are more and more important. They allow you to get free duchies whenever you decide to finish (so 3/5 provinces is easily winnable). Not really sure how to priortize this all, but i think this has a legit chance to beat bridges/BM. Also depends how invested bridges/BM will be towards caravans.
Edit: Here's a sample try. I also only grab 5 caravans to assume 5/5 split. I could've dipped in T14, but waited another turn to ensure all duchies. How to simulate, that's out of my realm though.
http://dominion.isotropic.org/gamelog/201201/31/game-20120131-125320-aa91169f.html