I agree with Zero I would really ask yourself which branch you will be happier with IF you don't get your top pick for career goals in either branch.
I would also I think in a way you do get an edge as a prior service from the CoCs ranking. If you look at historically, tech rated has the highest, but non-tech rated was the next highest. That being said, I thought I read that this year they did not ask cadets to sign off on the rated aspect for SFT like they did in the past few years.
I would also not only maintain good grades, but it is important to do well on the AFOQT because that score impacts you too. It is a chunk of the WCS. Thus, use this time to study the AFOQT. 1st impressions matter. As a sophomore in early fall you will take that test. So if you show up and pull a 90+ on the AFOQT, even as a non-tech, that will look better than you know because it is saying right off the bat you are a strong candidate.