I prefer MT couplers, but don't mind the Accumates. For extended draft gear it's very easy to make draft gear to fit from styrene. 3/32 by 3/16 brass tube will work, and is stronger, but the styrene can be glued to plastic floors. Also, it's easy to adjust the mounting height by changing the thickness of the top strip, and the Accumate has an offset shank, which works nicely on slightly low floors.
As for the trip pins, I leave them in, but if one falls out, I don't worry about it.
Note: DO NOT remove the pin from a McHenry coupler. You can cut it off, but if you remove it, the knuckle falls out, and you'll likely never find the spring.