I tend to agree with Mike, Krica, except for the following, and it is something you will have to figure out with your physicians.
I see you already have two strictures. Is it possible that the disease activity, while not widespread or acute enough to cause you symptoms, is quietly building scar tissue that will result sooner or later in obstruction from fibrotic stenosis in the strictures? If the disease activity is contributing to the formation of scar tissue then I think you and your GI need to have a frank discussion about the relative merits of getting more aggressive or taking the more moderate course you are now on.
In the meantime, do an honest assessment of your health status, regarding the disease. Are you really symptom-free? That would be great and would be a major factor in weighing your options. But is it possible that over time you have adjusted to the compromises we with simmering crohn's experience? Just because something is bearable, doesn't mean it is normal. Just a thought.
If in fact you are symptom free and your GI is comfortable that you are at a therapeutic level of imuran, like Mike says, it may be best not to tinker with what isn't broken.
Let us know what happens with the GI.
30+ years living with Crohn's.