Rule 42 of music; always show beat 3 in simple metre.
No exceptions. No exceptions.
I would defend the exception of the half note on beat 2 just because of its conventional use and clarity despite not being technically correct as shown in measure 17 of this:
About copyright I think my only big hangup with going with Newgrounds is that the game title being listed is Castle Crashers, which is not Newgrounds (so far as I know). Since you said your arrangement is of the Newgrounds version, I would like to see something pertaining to Newgrounds listed as the game title. That would solve the issue nicely.
Anyways, to the sheet itself:
-First page: I would lift the last line of music so it isn't cramming the copyright so much.
-Kind of all over the sheet, both hands, everywhere: I'm not sure I believe in having augmentation dots in both the augmentation position and the staccato position on the same note in the same voice at the same time (with the same hand). Sure, it's a staccato tenuto every time it appears here but I would still sooner see the rests just written out. It's less subjective and also less questionable. (Most questionable example of its use I see is measure 17 RH beat 3)
-Measure 41: You have articulation overlapping your dynamics. Spread it out some.
-Measure 66, RH: Here's a spot where what Ben said would apply. I wouldn't be against you leaving it personally however because it looks far more concise as it is rather than using a tie and comes at the expense of no clarity.
-Measures 97 and following, LH: Here's an example of misuse of staccatos. Write out these rests before slapping staccatos on notes that are either tied or under the effects of an augmentation do (as is the case here).
-Measure 153 and following, RH: More staccato stuff, you know the drill.
-I would spread the last two lines out a little more. That is, more space between hands for the last two lines.
-I think the last visual thing is the 8va at the end is a bit excessively long. I don't think you need the extension on it for a single note like this.
Again, due to circumstance rn I can't take a listen for note accuracies but fix those up and I'll be happier.
I can't even hear it and it looks insanely repetitive...