Why do you not like lash caps?
I use them to prevent the rocker arm tips from flattening out the valve stem tops out with high spring pressures and high RPM camshafts with solid lifters
As far as perfect rocker arm contact pattern to the valve stems back when Mopar had the drag race seminars prior to going bankrupt in 1980 they recommended the rocker arm contact pattern on the valve stem should start on the inner third of the valve stem and be in the middle of the valve stem at mid lift and on the outer third of the stem at max lift regardless of which Mopar V8 motor with single shaft rocker arms systems on them.
I shoot for right at .030 width on the valve stem to rocker arm roller tips Not zero width
That was before the Magnum SB motors came out and before anyone was making and selling the pair shaft rocker arm systems used today on the better high RPM valve train motors made today