Not to discourage you by any means, but 2 days is not enough to experience most of the rides and see most of the shows, etc. This is true even in the "off season." So just set your expectations appropriately. We always shoot for 3 days in the "off season" (and have generally timed it well) but even after 3 days I find myself thinking, we missed this or we missed that.
We're visiting again before GE opens for the simple reason that I'm fairly confident in saying there won't be a single week in the 2+ years following its opening that will be considered low/light crowds. I should caveat that this will be our first time using MaxPass, so maybe that will make up the difference in November, but I don't think it will be enough to offset the hoards of Star Wars fans descending on the park. Especially considering there's a good chance that GE won't have opened yet at DHS.
100% agree with others that you should get park hoppers. California Adventure is basically an extension of Disneyland, so hopping is quick and easy. Maybe you could get by with one full day at Disneyland and then park hop the other day. I can say with little hesitation if you do one full day at each you will, at a minimum, feel like you didn't adequately experience Disneyland. We're typically about 60% Disneyland, 40% DCA.
Prepare yourself that Downtown Disney is a much smaller version of Disney Springs. It's enjoyable for a few hours, but I wouldn't plan a big chunk of a day around that. If money was no object, I'd much rather have another partial day in the parks.
When it comes to crowd calendars, most of them have been less accurate at Disneyland over the last 2 years. Maybe that's from not taking economic conditions into account, or maybe it's because more people are paying attention to them now, so that's pushing more crowds into those periods of times. Regardless, I think they will be almost worthless for the 6+ months following GE's opening as nobody can adequately predict what will occur. But even the most optimistic fans expect significant crowds for many many months (or years) after it opens.
To sum it up, if you're dates are set in stone, then you just need to be prepared for heavy crowds and don't expect to get everything accomplished (even with MaxPass). Hopefully that will help you enjoy what you do experience, and then, on the off-chance that you get lucky and it's not crazy crowded, well, icing on the cake!