forest is actually obsoleted by the built-in subrepo feature.
bookmarks are always on now - the extension is now a no-op.
transplant is (mostly? it was for my needs) obsoleted by graft - a core command that's smarter.
mq I don't personally use anymore, because of bookmarks, rebase, and histedit
hsitedit - ships in the distro now, off by default (see below)
inotify - hg status /is/ fast. This makes it stupid fast even on absurdly large working copies (extension is subject to some race conditions though. I don't recommend it. bos is doing some work to make this faster w/o the extension).
acl: I think you're missing the point? It lets you have certain users allowed to push mods to a subset of files /without/ having to resort to multiple repositories (which are a hassle, even with submodules or subrepos).
Also, there's a reason some of these features are off by default - most users shouldn't be touching them. Having a barrier to using them has been (in my experience) a real benefit when trying to train newbies.
Also, some of us think pager is a misfeature - it drives me bonkers anytime git "helps" me in that way.