Estimating effect of filter on headroom
For an input with limited amplitude, the maximum amplitude gain of a filter can be calculated as the absolute sum of the impulse response
Scaling with the inverse of the absolute sum, will guarantee that your max output amplitude will never exceed the max input amplitude
In practice, this does NOT work well: It's a very conservative scaling that often results in bad signal to noise ratio and the input signal that would actually trigger the max amplitude gain is extremely unlikely to occur. Scaling this way leaves a lot of headroom on the table.
A better approach is to look at your worst case sine wave gain. Sine waves (or similar signal) do happen in music and audio a lot, so that's a much more likely scenario. Especially in your case, where the max is around 200 Hz. 
That still may not result in acceptable signal to noise ratio: in this case you can "eye ball" the gain at the most important frequencies and use a limiter or soft-clipper to manage the occasional overshoot. 


In your particular case, I'd probably go with -10dB scaling with a limiter (provided, it's implemented in floating point). At the end of the day this is a trade off between managing clipping/overshoots, efficiency, signal to noise ratio and max output capability. It needs to be optimized within the specific requirements of your application