the problem with 2:1 or as I like to call it risk to reward so that would be 1:2 is just from a math point of view, (ignoring your superior hit rate) most of the time it is going to hit your one risk stop before it hits your two reward profit. And that creates a real problem for an X:X risk to reward trader.
My target price is where I realistically would expect the price to hit resistance(or support if I'm short). I would view the price action objectively, in addition to indicators & volume, etc., etc. to make a judgement on if the momentum has stalled in my direction. The 1:2 is a metric I use to establish if the risk is too great to the reward. Once I'm in the trade, my actual target price may never be hit, but I will be using other indicators to judge when to take profits.