Requested feature overview description.
Please make the forward ("<<") and back (">>") pool buttons larger.

Why would it be useful?
While e621 has done a nice job on the "mobile" pages (i.e. e621.net/post/m/* and e621.net/post/p/* ), one very common usage on mobile devices is to read comics (pools).
Even on the mobile pages, the pool forward (">>") and back ("<<") buttons are tiny and frustratingly hard to press on many mobile devices.
Making them larger or in any other way more mobile-friendly would help people consuming art on mobile devices to do so with much greater ease and less frustration.

What part(s) of the site page(s) are affected?
I believe only the pool buttons on pages at "e621.net/post/p/*" would be affected.

Sounds good to me. Any increase in usability (that doesn't cause issues for others) is a positive move.

I'd like keyboard nav too.

Personally, I'd prefer being able to tap/click click the image to change pages, like everywhere else (but boorus [excluding panel's comic section] for some reason)

They can implement all of these features, and maybe add options to enable/disable each.

+1 for that, I can't see any harm in having bigger buttons and it just makes it easier for mobile users.

+1

I'm mostly using my phone to access this site (like now!).

They actually already changed it from just ">>" to "next >>" at some point which was already significant improvement on mobile but also on desktop when you didn't need precision aiming with cursor.

But mobile variation of site does need far more work than just pool navigation to it. It's mostly the same thing as regular site, just things rearranged and removed, which actually makes mobile navigating harder e.g. no link to parent/child post relations.

Turns out this would still be very useful.