Let me preface this by saying that I have no racing experience.

In all honesty, your post sounds like you want to move up to the next class. If you do move up, and you race next year, will it be in the same "sport" class again? If so, moving up now would not only give you a greater challenge, it might also set you up for greater success next year.

I'm very competitive by nature, so for me, a 1st place beginners finish that I didn't feel I had to work for wouldn't hold nearly as much weight or sense of accomplishment as would moving up a class in my first year of racing and finishing in a respectable place. That's just me though.

If you think there is still more to learn and benefits to gain by staying in the beginners class, then it may be worth your while to do so.