I would also love to see convolver support in Poweramp, since this opens up the use of corrective eq for individual headphones to get a reference frequency response (Viper DDC/IRS), which I think doesn't need to happen on a system level, but only when listening to music.
Another suggestion would be to open up a option to reorder different DSPs, for example on devices with sufficient cpu power, having sox resampler resample to 96k before engaging in a convolver, eq and such would be beneficial to quality,