Forcibly Finite
I've been telling myself since August that I would, eventually, come back and wrap up Infinifactory. But every time I actually think about it, I just can't even imagine myself enjoying the hours of work it'll take to do the five puzzles I have remaining.
At least of the puzzles currently available to me, they all require assembly from such a low level - like making a LEGO set out of only two-stud bricks - that the excitement of pulling off ingenious engineering becomes overshadowed by grueling tedium.
I would have to call these last few levels an unfortunate misstep for Infinifactory, and the culmination of an awkward pace (with multiple difficulty spikes) throughout the game.
But despite that, I have to commend Infinifactory on the whole, for delivering an impressive amount of great puzzle content. Not all of its puzzles are winners, but ... a great many of them are.
Better than: Shenzhen I/O and TIS-100 for sure; and probably SpaceChem, in general.
Not as good as: SpaceChem had a better difficulty curve (although its final boss was kind of terrible bullshit, too).
Just in time: for Opus Magnum! (hopefully coming out of Early Access soon?)
Progress: stopped at The Homeward Fleet - Fusion Reactor