Now that I've been playing with this ep for a while I don't think I'd play without it mainly because of the buy/build stuff more than anything else. I use the new furniture, windows, lights, and decor objects a lot.
As for the weather, well I've taken to making summers the longest season at 21 days, spring and fall at 14 days and winter at 7, I turn off rain as I too find it just too much and too often, plus I've suffered from the building/save bug because of it, it's not so much the rain itself as the fact it makes it so dark all the time, for a while I left hail on as it doesn't soak my sims, but that too makes it very dark during the day.
Winter looks lovely but a week of it is just about enough for me, still that week gives my sims the chance to build snowmen and igloos and whatever else they wish to do.
There are some things I do like though other than the new clothes and objects, the gift giving parties I enjoy, I like the way everybody turns up with a present and they all take their seats and chat with each other, it has a nice friendly feel to it. Costume parties are also quite fun. I like being able to write a love letter to a romantic interest and then getting one back from them, I don't like all the unwanted attention from already married men and women though.
The gifts are a pain but also a nice bit of money sometimes depending on what they send you, unless the gift comes from a romantic interest I sell it.
I wasn't too bothered about Alien abductions until I had a male heir in my townie dynasty game trying to supermax logic, poor guy was permanently pregnant during his young adult life and what's worse I had to send every single baby back, that got tougher with each one, I felt so sorry for him. Since then I have avoided doing anything that attracts them and if I have a logic supermax in my immortal one it will be a girl.