Yes, "persist in" refers to a strong determination in achieving the goal, and generally has a positive connotation; "insist on" is also a determination, but generally implies that the idea is contrary to another idea or fact, sometimes has a negative connotation.

persist =to continue to do something, although this is difficult, or other people oppose it insist=to say firmly and often that something is true, especially when other people think it may not be true also to demand that something should happen. =>Mike insisted that he was right. =>She kept insisting on her innocence =>He insisted I should take a taxi [from Longman]

The problem is that these two expressions both translate as 坚持 in Chinese. A better translation for "insist on" is 需求不断 . I do not necessarily agree that "insist on" has a negative connotation.