The console prompt seems to have a dark grey caret. It's fine for the included themes, but almost impossible to see in my custom theme. Therefore, for my first use of objc_util, I have turned it the same color as the caret in the main editor view. Before and after:

It's a major improvement with my theme. In the first example, you can see the cursor just barely if you have great eyesight and zoom in a lot.

This is the code, which I put in my pythonsita_startup.py

from objc_util import *
#Thanks to @JonB, he posted similar code a while back
def filter_subviews_by_class(view,objcclasstext=None):
    matching_svs=[]
    sv=view.subviews()
    if sv is None:
        return matching_svs
    for v in sv:
        if objcclasstext and objcclasstext in v._get_objc_classname():
            matching_svs.append(v)
        matching_svs.extend(
        filter_subviews_by_class(v,objcclasstext))
    return matching_svs

w=ObjCClass('UIApplication').sharedApplication().keyWindow()
main_view=w.rootViewController().view()
console_prompt=filter_subviews_by_class(main_view,'PA2PromptTextField')[0]
console_prompt.tintColor=ObjCClass('UIColor').colorWithRed_green_blue_alpha_(0.47, 0.67, 0.71, 1.0)