A few thoughts regarding the models and trying to forecast this one...
This storm made me think about how it could be a good idea to divide your forecast thoughts on the time period before the high res models come out (Days 4+) vs. the time period when the high res models will be on the storm (Days 1-3).
In the Day 4+ period, the Euro AI was fantastic and the clear winner in my mind with how it consistently brought the various pieces together at 500mb to produce the end result of Miller A from the gulf coast to the Carolina coast (baja wave / central conus trough dropping in / partial phase / positive tilt trough).
In the end, the Euro AI was a bit too suppressed with the storm track and too cool with temperatures aloft (an issue with most of the globals), though it was actually quite good with surface temperatures east of the Apps, as it had the cold air entrenched down into SCarolina.
But whenever there is a gulf low, we have to take into account whether or not we have enough cold air to hold off the inevitable warmth that it brings with it. In this case, at days 4-6, it would have been smart to say, OK, when the high res models get a hold of this storm, what are they going to do with it? For one, we could maybe anticipate that the baja low kicking east was going to be a heat pump on its eastern flank, pumping warmth out of Mexico and into the southern plains and southeast. And although we had some decent cold air over the Mid-Atlantic and NE with some fresh snowpack, there was not good, cold high pressure to the north (which many pointed out), and forecast thicknesses were high. So, there was a built in weakness there for the warmth to climb north. And when there is a weakness, we should anticipate that the high res models are going to take advantage of it when they come into view in the Day 1-3 timeframe, especially so when the precip is driven by warm advection in absence of a good, closed low at 850mb that has a southerly track, and with good cold air to the north.
Anyway, those are just some thoughts when looking back on this storm in hindsight forecasting wise.