Okay...IB charts pretty much suck. Some advise that we should use some 3rd party. Most of us do. Some say we shouldn't even expect to get charts from IB. Not sure about that logic. (Yes, I am paying for charting via commisions.) So, the question to me seems to be why is IB still throwing out some mediocre charting? Fix it or toss it. Makes the company look cheap.
TWS charts are adequate for someone who trades occasionally. They are also a suitable back-up in case the 3rd party software or data fail (especially while you are in a short-term trade). Personally, I like the bars width auto-adjustment. This is the part I miss in the charting software I use.