My guess as to why you don't have much in the way of human and dinosaur fossils together, and there seems to be more than one reason, would be as follows.
Humans have always lived near water for the most part; elaine Morgan in fact makes a fairly compelling case that we were originally aquatic.
That says that most of the places which humans inhabited prior to the flood are now beneath the waves. There was simply never as much water on the Earth before the flood as there is now. If there had been, then given the hotter climate of the hipsothermal, we'd have probably all drowned as you might note in the latest piece of leftwing outlaw-the-internal-combustion-engine garbage coming out of Hollywood.
Finding Cities in all the Wrong Places
Given standard theories wrt the history of our solar system and our
own planet, nobody should be finding cities and villages on Mars, 2100 feet
beneath the waves off Cuba, or buried under two miles of Antarctic ice.
Those interested in the city off Cuba should do google searches on the three words 'cuba', 'city', and
'Zelitsky' from time to time.
That says that we are, for the most part, now living in areas which would have been viewed as plateaus and sparsely if at all populated prior to the flood. That also says that you should not expect to find a whole lot of anything in the way of antediluvian (human) fossils lying around.
Moreover, it seems likely to me that, while there were leftover dinosaurs kicking around four or five thousand years ago, humans probably did not live in the main age of dinosaurs on this planet. In particular, I cannot picture humans living around raptors without modern weaponry. Midrashim in particular describes a number of animals such as the reem in precisely the way you'd expect leftover dinosaurs to be described i.e. as curiosities at a time just prior to and shortly after the flood.
I would GUESS that the main age of dinosaurs was somewhere backwards from 10K to a few tens of thousands of years back, but not 65 million.
In the case of Mishipishu, the water panther, we have an animal which has no adaptation for an aquatic life at all, nonetheless, after the change in gravity which killed off all the remaining dinosaurs and larger pleistocene megafauna, the stegosaur, or those of him left, tried to adapt by moving into the water. It obviously did not work out too well for him or he'd still be there in the Mississippi river.
The thread on the topic of dinosaurs and gravity is at:
http://
EvC Forum: Dinosaurs and the reduced felt effect of gravity -->
EvC Forum: Dinosaurs and the reduced felt effect of gravity