Similar to what @MarketMayhem mentioned, this is what I would like to see as a risk to reward calculator. Simple ruler or measurement tool that you could input the calculation value like 1:1, 2:1, 3:1, etc click entry drag to stop and it auto calculates the take profit zone based on the parameters set. Here is an example @MadCat of what I was thinking.
Something similar to this position tool from TradingView that calculates ticks to target, ticks to stop, and risk/reward ratio; can be adjusted by drag and drop; displays stats on hover or constantly if checked in settings.