Totally love Christmas since its a convolution of multiple inputs, not least of which is celestial mechanics, and not least of which is the bitter huddling cold that invites you to take stock of what's good. I could not give a fig's leaf how arbitrarily made up it is. It's got music that no other holiday has. It's been diluted since secular forces have been taking religion out of schools. So being an ex-JW and trying to get in on the (scientifically invalid but emotionally) vibrant experience that was missed as a kid is practically a no-go. The holiday has been sucked dry by the money changers and politicians (I say this as an atheist).
Thanksgiving lost its nationalistic or exceptionalist meaning, so it's not anything particular now. Secular excuse for kicking back. Eh. There's a bit of national pride to be gleaned, but what is the nation to be proud about right now? It's becoming a police state.
Halloween is too much of a grab bag or catch-all of detritus. Has no meaning anymore (not that Thanksgiving or Christmas absolutely do, either). I watch a good many supernatural suspense/thriller movies to get my dose of chills. No chills in Halloween.
Birthdays are a great thing to do if you remember them. Real life / exiting young adulthood has a way of shelving them, since their significance is inversely proportional to quantity.
Easter is tainted from Memorial - Never got up a good sense of envy about rabbits and easter eggs, since the pagan roots were kind of un-provocatively obvious and not hotly contested. At least Christmas pagan roots had some subtleties, niceties, grist for the supposition that ancient Christians may or may not have given gifts on the 25th, stuff like that. Easter's just kind of you and Jesus and little cups of watercolor paint and mess. Not engaging, unless you perhaps have kids.
New Year's is of course a secular accomplishment to partake in. Doesn't have to be any spiritual dimension to it, no gratitude to god, no forgiveness, no promises, no resolutions. Just a general satisfaction of a year under the belt, whatever that brought you.