G. Mark’s Answer
First off, what you've been told is correct. In most architectural assignments you'll often be designing a very small part of the entire project or building. Not to say that ME will not do the same in many cases, but you'll have, in my opinion, much more latitude. Obviously, there is quite a bit of variability in this, and these are generalizations, but in my experience, true. Second, and this is the most important consideration -- again, in my opinion -- you need to assess just how good a match your personality is for either of these. Since branches of engineering, by and large, operate under the same principles and concepts and overlap quite a bit, there will be a lot of overlap in the types of personalities that do well in those fields. I've said this many times before and I'll repeat it here. I tell my students that you will like what you do well and usually do well what you like. This is a good and convenient fact. As for matching your personality to those people that tend to be successful in any given field or sets of fields, you'll want to take a personality assessment survey, such as RIASE. These tests provide a large set of questions -- some of which are obvious in intent and some of which seem a bit odd -- and simply do a statistical correlation between your answers and those of people who are successful in a lot of different areas. Because of what I said before about liking what you're good at, it turns out that the results of this sort of survey correlates very well to predict your success in some set of careers. And because of what I said before, you'll also have a high probability of enjoying those fields that this test / survey recommends. So check with some guidance counselors or career advisors at local schools and colleges and find out where you can take one of these tests. The test is fun and you might get some very interesting answers. I, for example, was told that I would fit in well with scientists and engineers and mechanics. I was also told I matched up well with being a park ranger, which was a bit surprising to me. But upon reflection, it told me about aspects of my personality and preferences.