I know that the overlay displays current game fps and recording fps, but it would be handy to have the option to output a txt file for benchmarking purposes. So can choose to log Min Max and Avg fps, and complete frame times if necessary, so you can analyse a full benchmark session using 95th percentile rule. You should be able to benchmark with and without recording so you can assess the performance impact. Unfortunately I can't use fraps at the same as dxtory which would solve this issue.
There should also be a file that confirms that every frame has been captured at the desired fps, if there are dropped frames or spikes in capture frametimes this should be recorded in the file. If possible error messages should identify the cause of the such as cpu bottleneck or hardrive bandwidth.
Finally it would be cool to have a standard OpenGL or Directx program that can become the standard benchmark for users to capture (like the standard benchmarks you get in games) If everyone is encoding the same content this will allow any issues to be discussed
Maybe there are other ways to get to same solution, I'd be glad of any feedback