Ways to amass rep that positively impact the site.
There are plenty of vampiric strategies that one can employ. Those that overall don't make the site a better place to be. That don't make it a more effective place to get questions answered. I'll be talking about the ways that make the site work better.
I find that there are two general strategies to getting rep quickly:
Frequently visit "high-churn" tags
These are tags that get a lot of questions. Which means they quickly get a lot of answers. But the former means that, if you visit the site 20 times a day, odds are you will find a few questions that you can answer which have not yet been answered.
Naturally, this requires some significant expertise in high-churn fields, so that you can not simply quickly answer questions, but do so effectively. You can expect to get 2-4 upvotes on these questions, so you don't need more than 4-6 of them daily before you hit the cap. And it doesn't even matter if a couple of others slip in; as long as you're within the first 4 minutes of the question hitting the site, you stand a good chance of getting some upvotes.
Well, assuming your answer is correct.
Have significant expertise in a "low-churn" tag
Maybe this tag only gets 10 questions a day. Maybe only 4 regular contributors even check the tag, let alone know how to answer them.
Being able to serve the under-served parts of SO means that you don't have to visit very often, but it also means you get a lot more accepts, rather than just upvotes. So if you combine these two strategies, the 200 rep barrier becomes less important, since accepted answer rep doesn't count against it.
Indeed, if you happen to have a lot of various obscure knowledge, serving the under-served parts of SO can get you all the rep you need. Plus, you get to help people who might otherwise have not gotten help.
The downside here is that the low-churn tags are also more likely (by volume) to be from new posters who don't know what the accept button is, or don't even have the rep to upvote. However, those few regular contributors to those tags will likely hit you with an upvote when they see your answer.
There are also other tactics that you can employ in your answer. One that I do as a matter of course that just so happens to fit in is to add useful advice while answering. You should know the general idioms around a particular knowledge base and preach them where possible.
For example, if you're answering a C++ question where someone is gratuitously using
new, add a suggestion to your answer that they use a stack variable. If they're talking about writing destructors, bring up the Rule of Three and smart pointers. Experienced C++ programmers will almost always upvote you for that, and you'll be helping someone find programming techniques that they may not have found otherwise.
Overkill is another tactic. If you can't be first, then by God be biggest. Go into massive detail. Lecture the person asking the question.
You can't overkill on most questions. But you don't have to. If you're in a high-churn tag, a good bit of overkill can earn you 100 rep easily. Overkill doesn't work so well in low-churn tags, since overkill relies on many people seeing the sheer massiveness of your answer.