It would be nice if some of the sights were a little bigger, since it seems that some of them (F4U, for example) are smaller than "scale".
Are you having difficulty seeing the sights? Are you aware that you can adjust brightness, etc, to some extent?
Assuming that the sights are visible enough, going larger generally makes them less accurate. Larger sights often cover more of the target, which can cause issues. They can also lead to not being picky enough when aiming. Your bullets will go to the center of your sight , at your convergence setting, regardless of whether your sights are 1/16 of an inch or 10ft across.
What specific issues do you hope to fix with larger sights? Maybe we can help.
MtnMan