How big a change would this upgrade make?

I'm considering some upgrades to my system, and I wanted to ask if it will make a really transformational difference, or if it will be only a marginal step up. Not that I am unhappy with the sound of my setup, but like so many of us, I'm always looking for more if I can get it.

Right now, I have Joseph Audio Pulsar speakers, with computer audio as my source.

Suppose I made these upgrades (my current components on the left, new ones on the right):

Preamp: Arc LS26 --> ARC Ref 5SE
Amp: Pass XA30.5 --> ARC Ref 75
DAC: PS Audio MKii --> PS Audio DirectStream

At the not-small cost of ~$11k, would this upgrade chain be like night-and-day relative to my current stuff, or something much smaller?

Maybe one more question: if you could only make one of these upgrades, which would it be?
The only way to tell would be to have access to all 6 components and the rest of your system. Otherwise, you're just guessing. How do you know the Ref 75 is a better match than the XA30.5 for your speakers?
Keep your preamp, upgrade to DirectStream and get a more powerful ARC amp than the 75. Alternatively, you could get rid of your preamp, run the DirectStream as a DAC/preamp and get a more powerful amp than the Pass.

The Pulsars have low sensitivity and need some power. The effect of more high quality power is subtle, but musically important.
In my experience at the level you now have, great improvements are unlikely. As to which I would upgrade it would be the pre amp or the DAC. The new PS audio DAC has some very nice reviews. Most of all do you really like your speakers? They make the biggest difference over any good component IMO. Happy hunting and listening.
Wow! That would be an awesome system!
The reviewer of the ARC 75 (TAS? Stereophile?) claimed
this amp is unstoppable (seemingly unlimited power).
I'd be sure to audition with your speakers first.
Then try with Revel 208's or Bryston Model T.
Don't be afraid to crank it up as this is why you're
paying the big bucks (grace under pressure).
Keep us informed...
Most of all do you really like your speakers? They make the biggest difference over any good component IMO.

The speakers are great; I'm not contemplating a change there. Specifically, my listening room is better suited for monitors than floorstanders (12.5" front to back). I'm not sure I can find better monitors than the Pulsars even at a much higher price.