I realize this is a shameless plug, and it does not meet all the criteria the OP listed but for other applicants looking for similar schools they may want to consider;
The University of Idaho
OOS Tuition full cost w/o any scholarships is $18,000.00 +- a few dollars per year.
Public University
Well regarded Engineering and Business school
On Campus Law School, great resource for Poly Sci and International Studies majors.
Small Public School - 10,000 +- Undergrad population
Not a commuter school
Small College town.
8 miles from WSU, allows for may cross town class opportunities.
Only Div 1A Football stadium that is a covered dome, great when it's snowing.
Hosts all 4 ROTC Programs
Every cadet wanting AD received AD last year.
Great Greek system with an old traditional Greek Row.
Traditional old red brick campus.
So there you go, my biased plug for the U of I, I confess, that my older son graduated from there last year and my younger son is a sophomore this year. We do not live in Idaho. They both have loved the school, just as most kids love the school they attend.
Roughrider,
Just saw your last post.
Being a non scholarship cadet does not hurt your son at all in achieving his goals. The scholarship gives only one advantage, that is that a cadet can contract earlier with a scholarship. Being contracted would allow the cadet the opportunity to attend CULP or a summer training program. While these can add some points to a OMS there are other ways to earn those points as well.
Most cadets are non scholarship.
At my son's school, he was the only 4 year scholarship cadet when he started last year. By the beginning of this year they had given campus scholarships to 2 more cadets in his class. Of course my son's school is a smaller school with a smaller battalion which helps, these cadets were not competing with 50 other MS1's for the campus scholarships.
Once they are enrolled in ROTC they will all be treated the same, scholarship or not, what matters is how they perform in ROTC and school.