Where are all the transitional species?
This is an old, tired anti-evolutionary argument. The answer is that every single fossil we find is a transitional species. Unfortunately fossilization is an incredibly unlikely event, and a fossil surviving for tens of millions of years and then happening to be uncovered even more incredibly unlikely, so the fossil record simply doesn't contain every species that ever existed. We may never find the real ancestor of all modern birds, just cousins of it like Archaeopteryx. So what? The fact that birds evolved from dinosaurs is irrefutable.
The problem is the date for feathers keeps getting pushed back and there have even been early lizards found with what appear to be feathers.
I assume you're referring to Longisquama. There is good reason to doubt that those structures were even real, let alone feathers.
One massive gap is if birds evolved from dinosaurs where are all the tree dwelling dinos?
What are you talking about? First, the division between "bird" and "dinosaur" is entirely arbitrary. Birds, in a very real sense, ARE dinosaurs. We just draw an arbitrary line in the sand and say the things on one side are dinosaurs and the things on the other side are birds, but there's no hard and fast reason to draw the line at any particular spot. Archaeopteryx really doesn't look all that different from the raptors that came before it, and still has a very dinosaur-like head and no beak. Is it a bird?
Early birds were likely ground dwellers, just like the raptors they evolved from. We don't know precisely when tree-dwelling evolved, because we don't have enough fossils to be able to tell. I fail to see how this is a "massive gap"; it's a minor question at best.
Odds are birds branched off very early on and were a separate line of evolution so saying birds evolved from dinosaurs is kind of like saying we evolved from chimpanzee.s
Nonsense. Saying birds evolved from Archaeopteryx would be like saying we evolved from chimps -- not all that far wrong, but wrong. Saying birds evolved from dinosaurs is like saying we evolved from primates. Dinosaurs are a very, very big group, and there is absolutely no doubt that birds evolved from them.