The Hex (trap) bar is not superior to the barbell in any way.
1. Sorry about your shins.
2. The alternate grip problem is addressed with the use of the hook grip, or straps for non-competitors at work-set weights.
3. That a person can "deadlift" more using this device is both undemonstrated and irrelevant. There are ways of pulling more weight than a correct deadlift permits, i.e. rack pulls, but that doesn't make them superior to the deadlift.
4. If you think the lifter's body is "in the way" during a deadlift, you don't know how to deadlift. The instructions are here: Starting Strength: Basic Barbell Training | The Aasgaard Company
5. If anything, the trap-bar "deadlift" more closely resembles squat mechanics than pulling mechanics, with a more vertical back angle and the grip-strength limitation imposed on it. We're already squatting, right?
5. What other bars have I suggested the use of for primary exercises anywhere in print?
6. But the primary problem is this: what is the lockout position of a trap-bar "deadlift" vs. the lockout position of a deadlift? Think about this carefully.