We could integrate if it there are specific plugins or features that that would be compelling. “500 plugins” sounds exciting, but I expect that most of them are either not useful for video, or are redundant with the host of plugins that are already available to us through MLT and Frei0r.
As a philosophy for Shotcut, we require each filter that we offer to be curated and carefully designed for the user interface. You may notice in other forum threads that we sometimes labor over which parameters to expose and what the ranges should be allowed. Due to this philosophy, we would not create a single filter called “GMIC” that exposes all 500 plugins. Rather, we would curate the best/most useful plugins and make a unique interface for each one.
It does not meet well with plans to do more on the GPU in the future. It will already be a massive undertaking to just provide a stable GPU pipeline and port what we currently have to work on it. Trying to mix CPU and GPU is bad for performance due to non-unified memory. So, I am not sure.