All achievements are technically doable in the current version (a few that weren't were removed before release, you can still see them in the page source, commented out, if you're curious), but it'll take multiple playthroughs, and currently, quite a bit of guesswork. A better UI is already on the todo list for one of the next releases, so the trickier achievements are easier to figure out.
I quite like the keyboard navigation script, though it needs to pause itself if the player is trying to enter a name (a/s are pretty common letters), maybe just return early on document.activeElement.tagName==="INPUT"?