At bigger programs, you'll want to be concerned with the process of getting into the College of Engineering (or whatever it is called).
For example at PSU - just because you get admitted for engineering, doesn't mean you get into the CoE. The first 2 years, you are in pre-engineering major status. The spring of your sophomore year, you pick your top 3 disciplines to get into the CoE.
At PSU - unfortunately not everyone will get into the CoE. Most of the popular ones (ME, CE, NE, AE, etc) are under administrative control. What this means is only X students are admitted into the college - simply because there's just not enough resources to support every single kid trying to go engineering.
This is where GPA becomes even more critical. Say if the CoE is only picking up 150 students for ME, they will organize everyone by GPA, and will take the first 150 and all others with the same GPA as the 150th student.
As CollegeParent said, not all schools will allow you to count ROTC towards gen eds. I get 6 "general credits" for ROTC - that's it. My major is about 130 credits + 30'ish credits for ROTC, yielding me around 160 credits. Fortunately Army's giving me 4.5 years to complete the program.