I've got a very similar setup, except with a T430s rather than an X230 (and no new speakers, even though that's probably the thing I hate the most).

I'm probably not ready to replace it yet; it ends up being a terminal more than anything else and the performance is fine for where it's at. But... every now and then when I'm browsing, it'll slow to a crawl, and I pine for the fjords/something newer.

I've been holding back partly because it's still difficult to get more than 16GiB of RAM easily, but: is the Skylake-based Purism 13 a large or incremental step up in performance?