out of your choices i would select the beefmaster. the shorthorn influence would contribute to marbling ability, they should still maintain adequate ribeye, and the little extra backfat probably wouldn't do a lot of damage to yield grade. one breeder in our area has beefmasters- they have good conformation, disposition seems o.k., and they wean off heavy calves. also, don't think you would have to much eye trouble or fly problems. cons would be the ear, hide color and sheath.
hereford x that i've seen were tigerstriped.
murray grey x ???
you didn't mention angus over braunvieh. pros IMO would be polled calves, better ear, black hided (pretty much), improved sheath. cons IMO would be less muscle, higher yield grade, higher backfat.
good luck, ROB