Conti Terra Speed tire pressure dilemma.

[andy4g63]

Just finished a new gravel bike.
RIBBLE CGR SL with Rival AXS and Force combo and Zipp 303S and Continental Terra Speed 700x40 tires.
Bike came out great and looks great...

One area to be fixed though:

The other day I rode it for the first time and everything was great.
Irode it on the road using my LB AR56- wheels and Conti 5000 700x32 clinchers and latex tubes.

I rode at like 48/58 psi.

It felt a little harsh...

With the same wheels when on my road bike Canyon Ultimate CF SL
, everything feels great, super comfy and plush.

I understand that the gravel bike has a beefier fork, frame seatstays, etc.
But what do you guys think is gonna be a nice LOWER PRESSURE for my Conti Terra Speed, so it will feel more comfortable.

I was thinking like 32-33F and 35-36R.
I am 70-72 kg. and next weekend I have a gravel event,/around 90 km mixed 60-40% gravel/road.
but will not have the time to experiment on the road.

Can I go lower on the pressure, but still keep it fast for the tarmac.

P.S.From my only ride, probably it didn't help that I was sick/found out later/ and had a giant saddle sore, that was contributing to the overall feeling.

LMK, thx for your time.