Vassili Bykov explains why seemingly "little things" can't always be fixed right now - no matter how small you think the change is, there's almost always a snowballing effect of related changes that have to be made.
This is actually one of the constant tensions that exist between product management and engineering. In my role as PM, I want to see the product become easier to use and more consistent. This can often lead to my asking for "a simple tool" over here, or a "cleaner interface" over there. What I'm not always seeing (until it's pointed out!) is the downstream effect of those "simple" requests.
This is also where larger projects - such as Pollock are born. In order to really fix the current UI, it's not enough to simply tweak and tune - a general overhaul is called for. That general overhaul has its own downstream effects - all the tools have to be changed to match the new UI.