Aviation lateral transfers are super rare these days. Maybe 1-2 officers are picked annually... none were accepted for the August lateral transfer board and only one was taken in January. Aviation already has a tight career track and it's difficult and even risky for an O-2 to start flight school and meet all the qualifications to be selected for O-4 down the road. I know one O-4 right now who lateral transferred from SWO to Aviation as a new O-3, he did make O-4 but he's been on back to back to back "sea" duty/aviation assignments (DIVO, Super JO, and now Dept Head). That can be exhausting when you factor in deployments, work ups, OPTEMPO, family planning, etc.
For lateral transfer, not only do you have to be "accepted" and there's a board quota for you... but you also have to be released by the parent community. So you may have the best record in the world and there's a quota... however the SWO community might say no for releasing you to another community.
I would apply SWO only if you're fine serving that throughout your career.