Can I imagine myself as watching myself be there rather than actually seeing through my own eyes? Does it reduce the benefits?

No, it will not change the benefits. Start like that and keep going. I did the same. Eventually you will see through the eyes of your soul/self, looking through a camera lense from a place of peace, at the emotions and conscious minds termoil.
Good luck on your journey!

I can visualize certain aspects of my life. I use this practice for musical performance. More often, I imagine what I could have said after a conversation has long passed. I believe the more I imagine a positive future, the more likely it will come to be.

Nope, if you believe that lessen the benefits then it will.

In fact what you are doing is exercising your imagination/visualization skills. By seeing yourself from another perspective.

Also if it works for you, why kick it. Keep on at it with many goals you want to see achieve.

The more you do it the more you will have faith in the technique of looking at yourself from somewhere else.

I have done it too. Even to the extent of become an animal and seeing myself from the cats perspective. It's fun way to explore your imagination.

Xo, cheers to completing your goals in life.

My Dad used to read books of Lobsang Rampa. One specific book was about astral travelling. This in essence was about leaving your own body and seeing it from the outside. I believe this could be a brilliant way to see you as if another.