NE was the trickiest area for me, but 25A25A*Cache near a dash*[--------] (great clue btw) opened it right up. Nice theme, and I love it when the revealer is actually helpful to understand what's going on, which it did for me here.
Pretty close... and where to find the first parts of 17A17A*Rattlesnake variety*[-----------], 25A25A*Cache near a dash*[--------], 52A52A*Gotham City hotline*[--------], and 61A61A*Some studies*[-----------]
42A
Somewhat provocative
43A
Base for the cubs?
45A
Saline containers
48A
Media-monitoring org.
51A
"Kinda"
52A
Gotham City hotline
55A
Mets first baseman Pete
57A
Chicago-to-Detroit dir.
58A
Spielberg's production company
60A
Nutritional fig. found in "fiber datum"
61A
Some studies
66A
___ Ali, sports documentary
67A
Flip over
68A
Bread and butter
69A
Lou Gehrig's disease, briefly
70A
Euphoric
71A
Tiger's muzzle
Down
1D
Catcher for the marlins?
2D
Brit's college
3D
Chai, literally
4D
Pillar of Community?
5D
Better half, so to speak
6D
Designer Gucci
7D
Troubleshoot
8D
Prove useful
9D
Insta' upload
10D
[For shame!]
11D
Way to heat up your sushi?
12D
Region in Spain
13D
Fully-loaded
18D
Evening, commercially
21D
Unmask
22D
2-Down2DBrit's college[---] times three
23D
Native American tribe that anagrams to a breakfast chain
24D
Clickable image
26D
Word with history or tradition
27D
With "The", nickname actress Theda Bara earned for her femme fatale roles