I don't have write access to this repository, so here's some maybe-useful notes:

• Comment where @ldpl attached the 50k stations save: Change: Non-rectangular sparse station catchment area OpenTTD#7235 (comment)

• There is also the Wentbourne save. I'm quite sure it's sourced from the Savegames forum on TT-Forums, but couldn't find the original thread last I looked.

• The two most interesting performance gains from the k-d tree patch directly are probably map panning performance with a large number of viewport signs, and AI speed gains from tile-town lookups. It also opens up the possibility of more new features depending on tile-town lookups being fast.

• Write something about how old "exploits" are fixed, and generate some discussion about whether they were really exploits. (Sparse station catchment areas, and building rail out to oil rigs.)

You should have write access to this repository (in fact, to all OpenTTD repositories). It even says so next to your name ;) So I suggest we try to fix that ;)

Are you sure you don't have write access? Where did it fail?

https://github.com/OpenTTD/website/blob/monthly-dev-post/_posts/2019-04-01-monthly-dev-post.md
There is an Edit icon on the top right. You can click that, make the changes, and commit. Or at least, you should be able. Let me know where you get stuck, and let's take it from there!

Are we talking about nmlc as part of OpenTTD stuff?

16-cargo support has come up in forums a bit: OpenTTD/nml#15

@andythenorth I don't see why not. It's now being maintained under our umbrella.