Hey there, this is my first post here but I had to chime in because I live just a few minutes from the East Branch of the Brandywine and Indian Run. I just moved to PA from Arizona this past June but since getting here I have spent a decent amount of time on the Brandywine and let me firt say how awesome it is being here in a place where you can hit good trout water in a few minutes - when I lived in Phoenix it was a 2 hour drive to the nearest wild trout water.
Anyway, I have caught both wild Browns and holdover Rainbows in the Brandywine all the way up to Glenmoore which is well North of the DHAO area. I think the Browns do tend to hang around the confluence with Indian Run - at least that's where I have caught them and Indian Run does hold a small population of wild Browns.
What I have found on the Brandywine is that you can typically expect to catch 10-15 creek chub or sunfish for every trout caught - at least outside of the DHALO area and at times when there have been no recent stockings. While I'd rather catch nothing but wild Browns the bigger creek chub do put up a decent fight and seem to take a fly aggresively in all sorts of weather. Here are some pic's of Brandywine/Indian Run Trout that I have encountered. All of these came from outside the DHALO section.