Advanced DC kind of clumsy?

In my opnion what's happening to you must be a 'bug' or technical anomaly and should therefore be reported as something to fix. My experience with the ADC seems nothing like yours; it works exactly as intended including the intemiable ship que wait while every other ship passes through the slot leaving yours for last, no matter the proxmity. The timer has never even come close to running out and at it's worst ( such as when a Beluga or some other enormo-ship passes through) it's about a 75sec wait.
With what you're experiencing I'd hit tech support up.

Anybody else tried using the new ADC with a speedy ship such as, perhaps, a Viper 3, Eagle or iCourier?

My Viper had a spare slot and, well, I thought I'd give it a try.

It has a nasty habit of slamming me into landing pads at around 300m/s.

I think it's suppoed to descent at speed but then hover above the pad before landing.
It does do this sometimes, particularly at stations, but landing on planet surfaces (regardless of local gravity) is just bloomin' brutal.
Anyway, I just had the ultimate consequence of this when I allowed the ADC to land me (in my Viper, without a shield) at Lei Chung's base and... splat.
Rebuy. :(

The half-million credits rebuy isn't a big deal and it's not a show-stopper for the ADC cos when I do have a shield fitted I don't suffer a lot of damage but I don't think it's "working as intended" when the ADC face-plants your ship into the pad hard enough to destroy it, right?

Oh, while I'm at it, while I was leaving a station, just prior to this, the ADC kept me "waiting in queue" until the timer had counted down to 24 seconds and then I manually throttled up to get out of there.
The ADC wasn't showing any inclination to get me out of there (it was a busy station) but I don't think the "queuing system" is working correctly when various ships can complete their exit from a station while you just sit there, waiting to get exploded for loitering.
 
I've had it try to land my Corvette facing backwards twice.
Just hovers above the pad facing the mailslot.
Both times was very busy stations, lots of players.
 
I've had it try to land my Corvette facing backwards twice.
Just hovers above the pad facing the mailslot.
Both times was very busy stations, lots of players.

The regular DC did that to me a couple of times in my Cutter.

It'd perform a flawless landing - just facing the wrong way - then take off again, spin through 180° and then land again.

Kind of reminded me of this:-

 
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