True...you'll probably increase your responses by posting a photo of the cow, but generally speaking, you'll maximize heterosis by mating any British breed cow to a continental breed bull. I'm a Simmental breeder, so this sounds biased, but the REASON I'm a Simmental breeder is because of how our first crossbred calves performed compared to calves sired by other breeds. And our cow herd at the time was all British, black, black baldy & Hereford cross commercial cows. I like Simmental better than most of the European breeds because of their advantages in maternal value and their docility. And it really is kinda like magic on a good Angus or British-bred cow. I don't think you'd be disappointed if you're looking to make any type of market or breeding animal, but especially replacement females.
Give it some thought, and if the idea appeals to you, I'd be glad to talk more about specific bulls.