IMO , 75 psi cold isn`t too high . Mine runs 80 to 85psi cold , 57to 60 psi at 200 degrees
oil temp and 35 to 40 at idle , hot . I run 15W - 40 Brad Penn street and track . Is that 30 psi at idle or another rpm ?
Since you`re up North where it gets a little colder than here ( SC ) , you may want to go with a 10W - 40 for Fall and possibly 10W - 30 for Winter .
Just a thought .