Given your requirement
My priority is keeping lambing simple (so no combos that result in lambs that are likely to have to be pulled), retaining hardiness (we are quite high up) .. LOVELY fleece and an acceptable carcass.
I'd be looking at a Shetland dad and then a meat breed on the outcome of that. We've been finding Dutch Texel to be better on the no-pull lambing front (though we do pick tups with narrower shoulders and less exaggerated backsides) and to have very nice fleeces.
So far - limited experience over two years - I have been very impressed by the Shetland Xs - there seems to be a lot of hybrid vigour there

This being Shetland crossed onto Manxes, Charollais-type commercials, and a Shetland x commercial ram lamb on Shetland Xs, Manxes and Dutch Texel x commercials. (Also BFL x out of Shetlands, although you won't be wanting wimpy soft BFLs where you are

)
I don't know much about the Beulah, though, so I'm not sure about the start point in terms of carcase.