The big thing that's going to make you standout is obviously clinical performance. Any student that comes in, listens, follows directions, works hard, and has good clinical presentations immediately turns heads. Because most students fail in one of those areas. They either work hard and try to impress people but don't take the time to listen; or they give terrible presentations; or they are more interested in socializing than working. Be the complete package clinically, and your SLOE will reflect it.
You are right, things are getting more competitive, and I think they are about to get more competitive for AOA spots, because I think you are going to see over the next 2 years very few AOA spots. Many programs are looking to quickly switch to the ACGME, and when that happens, they have the option to just be a 3 year program and only match via the ACGME. While I love taking AOA students, having a 4 year AOA track and a 3 year ACGME track is way too complex, especially when you consider its only for 3 more years or so and after that its all ACGME and a 3 year program after that.
So what I forsee is, as many of the programs get accredited in the next 1-2 years, they are going to just exclusively match in the ACGME match, which will dry up the AOA spots altogether.
Do I know for certain that is going to happen, absolutely not. Its just my opinion based on the trend I'm hearing. And its absolutely what my program is trying to do. A few weeks ago, I didn't even know this was going to be possible under the single accreditation system, but by everything we've been recently told, it is, so we are marching forward as fast as possible. Always good to be an early leader rather than a late follower IMO.
That doesn't mean DOs will have a harder time matching. It just means they'll have to match via the ACGME match rather than the AOA match. The benefit to them is, no more 4 year residencies for the most part unless you really want to go to a 4 year program.