Flew the 1900 for about 1000 hours in the 121 world. We did NOT have autopilot installed on ours, but I heard that autopilot is an option. I flew both the C and D models. The C had no glass at all. The D had a very basic EFIS. Since you are asking about the D I'll go more into it.

1. No AP on the ones I flew
2. FD was avail, but would not capture altitudes so was basically only useful in cruise or on an ILS.
3. We had no auto anything...no anti skid, no power steering, no FADEC or any other protection for the engines....no 1 button/1 knob engine starting...
4. Airplane is basic enough that if it is broke it is broke....it doesn't get confused like some other planes
5. Flies super stable once you get it trimmed out
6. Can hold a ton of ice
7. Once again noting is automatic so you have to turn on the ice protection. Boots don't have an auto mode you just pop em when the wing looks too scarey....on a side note the longer you let ice build up the better it breaks off....I never saw it truly "bridge", but if you blew the boots early not much ice came off.
8. Not sure if this is fleet wide or was more specific to my company but it was kinda common for one prop to go into ground idle during the flare if you hit idle before hitting the ground...that got fun fast.
9. Just remembered this and wish other planes I have flown had it...but you could preselect a course for the CDI and then when you got to the turn flip it to active and then you had time to set up your next turn.

All in all it was a good plane. It was easy to fly and straight forward. Was the only plane I flew that I felt was slightly overpowered which was nice. I would fly one again in a heart beat if the pay and QOL was right. V1 cuts were sporty....especially if they failed the autofeather as well.

Its been about 6 years since I flew the 1900, but thats pretty much what I remember about it.