So I've been checking out alternatives.
I wanted something that worked fast, offered all or most of PieCrust's features that I used and was fun to tinker with so I could implement the missing features.
Since most dynamic languages are slower than the compiled ones, I preferred something compiled, which reduced the number of options significantly. Furthermore, even though I love Haskell, it can be quite difficult to get it to compile on shared hosting.
This more or less left a couple of options in go. And my companion was found in gostatic, a very fast static site generator written in go, using golang templates with a small code base that was quite understandable.
As it is written in go with only three dependencies, it's quite easy to compile and get working. It didn't offer all features that I wanted (such as pagination, including files and assets), but the source code was small enough so I could implement all features and a compatibility layer with PieCrust (so I did not to have to rewrite all pages and posts).
And, as I was updating the site, I also added lazy image loading for posts, quite useful for my travel posts with lots of images :)
As for now, it seems to do pretty well for my setup, generating the complete site in 10-20s on dreamhost (the large variance is due to it being on a shared host), and less than 5s on my main computer, compared to PieCrust's +60s.