You are relying on the God of the Gaps argument. Archaeopteryx is a fossil leading from dinosaurs to birds. If we had no Archaeopteryx fossil, you would complain that there was nothing to indicate transition between dinosaurs and birds.
Now you complain that there's nothing indicating transition between dinosaurs and Archaeopteryx.
When such a fossil is uncovered, you will complain that it is a "stand alone" animal with no transition to dinosaurs before or Archaeopteryx after. All of which is quite unnecessary. The relationship between birds and dinosaurs does not rest solely on Archaeopteryx, or any other fossil. It is obvious from the anatomy of birds and of dinosaurs and from genetics. Even domestic chickens are just one mutation away from bearing teeth.
Fossils are but one part of the evidence for evolution. The fossil record is extensive, but patchy for obvious reasons. Only a tiny proportion of all species, let alone individual organisms, are represented in the fossil record. But even if there were no fossils at all, the fact of evolution would be obvious from the genetic record of extant organisms, from the geological record of deep time and changing ecological conditions and from the observations available of evolution in the short term.