That one you've got isn't bad, I kinda like it actually. The only thing I'd consider instead of a curb strap I'd use a slober bar. A slober bar holds the two shanks together so that when you neck rein it turns the bit more correctly in their mouth - I can go into details if your interested. But I love the short shanks and high purchase, that's barely a step up from a snaffle if you don't use a curb strap - it's a more clear communication without being overly strong when compared to a snaffle. :)
I'd use a slober bar instead of a curb strap honestly (not that they're mutually exclusive you could use both, but I don't see a need).