Right now, what I think you were asking is if the length and detail of a story changes when you have more casual readers instead of dedicated, and the answer is it really depends. Like I said earlier, you'll unconsciously improve the more chapters you post, just because your audience will tell you how to improve. Otherwise, in your newest post, you're asking if you should increase the length and detail of your chapters, am I right? If that's the case, then that depends too. As you can tell by the other posts in this thread, there's not really a final word when it comes to chapter length. Some people prefer longer ones; some prefer shorter. And as for detail, basically, how much you'll need depends on a case-by-case basis.
But honestly, I think a number of the problems you're facing in getting reviewership lies in the fact that you're working in the least active fiction forum on Serebii. Not too many people venture in there, and besides that, not that many people on a fanfiction board (generally speaking) read original fic for a whole list of reasons. So you're actually working with a disadvantage that has less to do with your chapter length and more to do with, unfortunately speaking, what your story is. Only way you can fix that is by being very active in getting attention: post in the review games, VM reviewers for review requests, and so forth. Sorry about that.