Mary, what you describe is close to classic dispensationalism of the Scofield variety, which is easy to critique; it has been replaced in large measure by a progressive dispensationalism that is less obviously wrong. But it is still dispensationalism, and you will find both varieties to exist in cessationist and non-cessationist forms.
But the key point here is that the identification of a difference is not the same thing as dispensationalism. If it were, all Christians would be dispensationalists for not offering animal sacrifices; Moses would be one for restricting sacrifice to the tabernacle; the author of Hebrews would be one for saying that in times past God spoke in diverse ways but has now spoken to us in his Son. There are differences in how God executes his saving purpose; there is no difference in what that purpose is or the essential basics of how it is appropriated. By faith Abel, Enoch, Noah, Abraham, etc.
The question of cessationism is a different question from dispensationalism. The real issue is whether we are part of redemptive history or ecclesiastical history. To put the same thing another way, has God laid the foundation and we are on to superstructure, or is the foundation still in progress? There is some dispute as to what pertains to the foundation and what to the superstructure; how you determine that depends on theological method.
I think you have identified something genuine in pointing to literalism as characteristic of your approach, but the contrast is not between literalism and theory: literalism is a theory, after all. And of course to say that one is being literal can beg the question. The question is, how is the letter to be understood? Many premillenialists give the preference to a physical understanding, though as far as I know none to such a degree that they have built a house on the Mediterranean coast so they can sea the beast rise out of the see. In other words, they recognise that there are definite limits to how physically things can be taken.
Amillenialists don't (or shouldn't) admit that they are not being literal. It is a literal interpretation to understand the letters within the kind of literature they are. Poetry and instruction manuals don't use language the same way, and an insistence on interpreting a metaphysical poet the same way as DOS 6.0 User's Manual will not aid in understanding, nor will it be genuinely literal; on the contrary, it will distort the author's intentions. This seems very difficult to some, but I think that is in many cases a result of learned ignorance. The uneducated and illiterate it's been my privilege to know use and comprehend metaphorical language with little difficulty, as long as they have a point of contact for the metaphors. It is those with some education who have a harder time with that. "A little learning is a dangerous thing."
Also involved is a recognition that theology is a post-canonical enterprise, of a different genre than revelation; and that inference is an indispensable and inevitable tool, so it needs to be used rigorously and well. Finally, a commitment to let each text speak on its own terms but to correlate harmoniously the results of all texts is essential to having a genuinely Biblical systematic theology.
Differences can still arise among those who affirm the methodological principles I've set out, in part due to human weakness on all sides, in part due to differing plausibility structures and driving commitments, and in part because not all things are alike clear in themselves. But many of the big differences and frustrating disagreements among Christians arise because we don't share the same methods and are often entirely unaware of the questions of method.