A threshold would still help as it is much better to see a strategy not starting (and a message such as "warning: attempting to load too much historical data, check your local data and configuration") than just exceeding the quota limits and having to wait for one week before trying again... Ok, maybe not the highest-priority enhancement but not useless either. In fact the API should be doing that.
Anyway, I will try updating my local data from other sources and then give it another shot.