Hi,
As a recent convert and somebody who was very cautious about implementing PipeWire and also someone who was fairly annoyed and vocal about having to adopt something 'new' over something that was in my experience fully useful and functional I'm hoping I can clear the air a bit..
IF you embrace PipeWire's milestone 1.0.0 release in it's fullness which encompasses ALSA, JACK and PulseAudio functions and IF you have it set up properly which will include creating system links so JACK applications silently connect to pipewire-jack as well as using one of the many new 'pipewire-metadata' UI's and lastly installing qpwgraph then you will have all the functionality of a traditional qjackctl/JACK system and then some.. Keeping or continuing to use qjackctl and JACK will create more confusion and indeed create a virtual and visual spaghetti mess..
The metadata UI you choose (upcoming AV Linux will have it's own) is how you set the quantum (buffers) and sample rate and qpwgraph is how you make and see the connections. There is no need for qjackctl or JACK itself in this scenario... And things will be actually be EASIER..
When properly set up, pipewire-jack is running at boot, if you fire up Reaper, Ardour, Qtractor etc. and select your JACK backends then presto all is running instantly.. No opening qjackctl and THEN selecting the explicit device and settings THEN starting JACK.. With PipeWire it's already there waiting for you to present a set of pins to connect it to... If you know ahead of time that you require a different buffer size or sample rate then simply set that before you start Reaper or Ardour etc...
If you accept this is a new way with new methods and commit to understanding it you will find it's actually simpler and NOW has equivalent latency performance potential. If you cling desperately to half of the old system and don't set PipeWire up optimally then you will have an unsatisfactory half-baked mess.. I'm old and pragmatic and if I could do it anyone can do it!