It's still quite do-able, you just have to watch where you are now, and your pulls. You also can't get 1-2 groups, depending on the spawn. It's also a tad bit slower due to patrols, but I've still done <30 minute runs.
You can make it to plains with no problems, just like before, the skeleton from first chamber can be avoided easily. Nasty part is when you get there, maybe my bad luck, but almost half the mobs from plains were covered with skeletons