I don't think the timeframe should have impact on the difficulty.
All suggestions in pre1500 timeframe are hard to resolve due to the lack of sources. 1500-1700 are a bit easyer and so on.
Also some regions are easyer than others due to good access to online sources.
With 591 we have 2 profiles, that are not connected on wikitree and are on FindAGrave. If both profiles are properly sourced this should be a trivial suggestion to correct.