OK, I'm going to stick my neck way out, and give a bit of a different perspective on how/why IB does business the way they do.
First off, I'm not trying to convince anyone of anything, only sharing another possible way to look at the situation.
Secondly, I'm not affiliated with IB in any way, other than as a client.
I've spent almost 30 years in the world of dealing with customers. In my case, retail. But, I would submit a customer is a customer. It took me almost 25 years to figure out something that, I truly believe, is the way successful businesses (read that profitable) will have t be run.
The key element is this: choose your customers. Corrollary: the customer is NOT always right. I've done some things with my business that you wouldn't believe. Raise prices big time. Reduce hours open. Tell people they're not appropriate to my business. I run it how I want to, not how my customers want to.
Guess what has happened? I have had the largest and most consistant growth I have ever experienced. And no end in sight. I see IB doing the same thing to some extent. They're doing what they want, the way that makes sense to them, and by doing so have created a significant and loyal client base. You cannot be all things to all people, as a matter of fact trying to do so would be financial suicide.
This may not sit well with those in the audience that have been weaned on the "customer is always right" mantra. But the cold hard fact is IB exists to make a profit. Whatever way they can do it that best serves "their" needs is appropriate in a free market.
So if you find more to dislike than like about IB, I suspect they don't care much if you go elsewhere.