I don't think I've seen this theme before. At first I thought it was counting down, but in fact we have increasing fractions from one fifth to the whole. I like all of the theme answers, although FIFTHELEMENT requires the clue to carry the "The" of the title. Frankly, four out of the five answers really require that definite article to be complete, but only the first supplies it in the clue. I like WHOLESHEBANG the best of the lot.
1A: Cover during a rain delay (TARP) is once again a very reasonable start to the puzzle, and I'll give it a B. There are two very nice 10-letter down answers in 11D: Hawaii's nickname (ALOHASTATE) and 29D: Paintings with fruits and vases, often (STILLLIFES). I like the three straight Ls in that one.
I never liked ODIE, either in the comic strip or in a puzzle. Otherwise I have no quibbles. Nothing much to exclaim about in the cluing otherwise, so for my favorite clue-answer pair, I'm going with 22D: Like a squirrel's acorns (STASHED).
Overall, it's a NICEONE. And the Pats won, so that's nice also. Good night!