Thanks a lot !
yep our addons doesn’t collide ! 
And i tried yours ! great one, a lot of improvements in the practical field of the sequencer !
I love being able to fast forward/backward ! that’s really great
About performances, i agree, but i tested again few days ago the open source editors out there (kdenlive, openshot, shotcut) available on windows, and to me, they aren’t really stable, and the one-timeline per project is really a downer… So i’m gonna continue to try to add some functionality to blender !
I just finished a little side project on it, and it is robust and stable to work with 
(the project : Speeches - 2d/3d short animation)
cheers, and thanks for your powersequencer addon !