Ok, you are looking for the 50/50, but also the 75/25 and 25/75. That's a reasonable request. In fact, I'll give you 2 on each side.
Now let's call the archeopterix the 50/50 transitional. It's the best known one and is considered to be right on that line of dinosaur/bird.
Now, on the dinosaur side of that, we have:
Anchiornis - Wikipedia, the free encyclopedia a feathered therapod which some once argued should be considered the first bird. We also have a remarkably well preserved specimen to the point that feather coloration could largely be determined.
Juravenator - Wikipedia, the free encyclopedia More dinosaur than Anchiornis, but still a feathered theropod. These feathers are rather primitive proto-feathers and at least some parts of the body had dinosaur like scales as well.
On the bird side, we have:
Confuciusornis - Wikipedia, the free encyclopedia an early bird which still retained claws on it's forelimbs. It's the first bird we know of to have a true beak. It was probably capable of only limited and possibly no flapping flight, but appears to be capable of soaring flight. Initial height for this may have been obtained by climbing trees.
Ichthyornis - Wikipedia, the free encyclopedia another primative bird, but much closer to modern birds. No functional claws are present on the forelimbs. It appears to have been a strong flier with a modern breastbone and wings.