How much editing can one ethically accept from one's advisor on a fellowship proposal (e.g. NSF/NDSEG/etc.) I'm applying for graduate fellowships right now (I am a first-year graduate student in a STEM field), and am preparing to submit the application. My advisor has been helping me out with it for a while, and at one point, he took my draft of my research proposal and made some somewhat significant edits to it. He added several paragraphs, deleted some of my wording, added some sources, and so on. Altogether, at least half of the text in the proposal—a lot of it is figures—has been written or edited by him, while half the text is still mine (and I made the figures and the general outline of the proposal).

For obvious reasons, I'm uncomfortable asking him whether or not his contributions are too substantial (I don't want to say "I think you did too much of it, so I'm going to change it back" or to do so behind his back), but at the same time, I'm cautious about whether or not it's unethical to receive that kind of help on the proposal for my fellowship application, because I'm not sure how these things typically work.

So, is this something that typically happens with these kinds of applications, and is it unethical/immoral on my part to use such a proposal (i.e. something that gives me any kind of unfair advantage)? Or, am I thinking of this too much like a competition that requires solely my efforts for my submission?

Edit I just want to stress that when I say about half the text was written by my advisor, I mean that I initially wrote the paragraphs in question, but they were substantially edited to get the idea across in a better way.

On that note, would it be appropriate for me to further edit his edits? At that point, though, I feel as though I'd be editing it just to avoid acting unethically, not to improve the proposal. Basically, what action would I take in order to ensure I'm not acting unethically here?
You apply for money and your adviser will profit from getting you granted the money, too. He will get some research he is interested. Why shouldn't every adviser support his student in that way?

You should also learn how to write proposals. Not just by writing it, but also to give it the finishing touches and fixing the issues you could not yet identify yourself. That's why its good to get the feedback and support you received from your adviser.

I don't see it unethical at all. It would be problematic if you could not perform the research you describe in your proposal or know it will not work or know someone already did it.