Yes, this needs to be implemented. If I create a sequence that I like, I'd want to try it with a different synth presets, but then I have to recreate it again from scratch.
The Pigments sequencer is one of the most powerful on the market, but lack of independent seq presets makes it value a lot less.
It is a common and very convenient feature on many modern synths to be able to save sequence presets independently of the main preset, and then load the sequences as needed.