Hypothetical question about choosing optics for rifles

Do I have these optics on the wrong guns?

Should I put the 1-4x on the SBR due to the stiffer, heavier barrel, or the SR15 which has a lighter profile barrel, since it will have higher muzzle velocity? Both guns have FF, hammer-forged barrels.

The SR15 is super light and fast-handling with the Deltapoint, which is desirable for obvious reasons. It seems counterproductive in a way to add a heavy optic and mount to it, if the benefits of the magnification are reduced by the light barrel profile.

The 11.5" BCM sbr has a heavier barrel profile which, in the realm of the 1-4x optic, serve me better at distance. The gun is already a little lighter than the SR15, so a heavy optic doesn’t seem to set me back as far as it does on the longer gun.

I haven’t had the chance to shoot the guns in this configuration, so this question is mostly theoretical in nature.

For my intended purposes, the SBR would get an Aimpoint and the KAC would get the scope. The 16" barrel has a longer reach and therefore would get scoped.