The overall flame charts just don't provide the immediate "Here's what's wrong" you need from a chart.
Charts should be simple enough to quickly get an idea of whether the thing you're looking at is "Good" or "bad" and if "Bad", quickly see where the problem is.
So my (and I guess your) workflow is then to fix the top-X hot paths, and then re-profile, etc.
The attraction of flame graphs, as I understand it, is that you can get the same information without the need to iterate. Which is obviously very valuable if you're operating on single-shot bug reports, but... how exactly? (Not a question directed at you, obviously, but more towards the general discussion)
In some cases it's not that helpful if you don't have the right type of problem, eg I was troubleshooting some higher level stuff (SQL) and looking at stored procedure invocations and a two depth invocation doesn't tell you very much.
For me a FG is more about sounding out the problem and understanding what the scope of what is possible more than fixing an immediate and obvious issue.