Marginal Gains, Goodyear Connector 45 to GravelKing ss 35

My Camino came shod with Goodyear Connector Ultimate 700 x 45. As a bang average pootler I am pondering changing to Panaracer GravelKings semi slick 700 x 35 as I switch to more road/all year cycle trails over the winter to avoid the deep brown stuff.

Putting to one side the ritual slagging off of GravelKings, will I actually notice much difference in terms of miles covered/speed for a similar energy input for the additional expenditure?

I accept tyre pressure will have a significant influence.

I have been running various GravelKings, Slick and SK in anything from 32 to 47mm and have never had an issue. Currently have 32 and 35 slicks on two bikes, set up tubeless and, for me, they have been perfect. I have some 35 Semi-Slick on standby for when I need to replace. I imagine you will certainly notice a difference from the Goodyears