12.04 and earlier versions always had the option for full disk encryption with dm-crypt, but you had to use the alternate install CD with the curses installer. It wasn't complicated at all. All they did with later versions was to roll the option into the standard live CD installer.
Regarding bug fixes and the need to stay on the upgrade treadmill, it's much easier nowadays to stick with LTS versions since they implemented the LTS enablement stack (https://wiki.ubuntu.com/Kernel/LTSEnablementStack). Essentially it's the kernel and X.org of the current release backported to the LTS release, so you don't miss out on new hardware support while getting all the bug fixes and stability that come from the LTS.
That being said, however, I'm finding 12.04 to be extremely buggy when you're using Unity+Compiz.
I've got one box running 12.04 and one running 12.10. Unity+Compiz is definitely buggy for me on 12.04, but they managed to make it worse on 12.10.
I really cannot fathom what is going on at Canonical. I get that they want a more friendly UI, because that will create a better user experience for a broader set of users. I even use Unity, and like where they're going with it. But can't they see that creating a flaky, unreliable experience is not actually helping? And that they're undermining Linux's major strength, a reputation for reliability?
By all means, Canonical, keep innovating. But stop breaking shit along the way. If the goal is a better user experience, make sure you're actually delivering a better user experience before releasing.
Most people seem to say that 13.04 is smoother and more stable than 12.10. Canonical seem to have their ups and downs. I don't think desktop Linux has ever really had a great reputation for reliability, though.
Regarding bug fixes and the need to stay on the upgrade treadmill, it's much easier nowadays to stick with LTS versions since they implemented the LTS enablement stack (https://wiki.ubuntu.com/Kernel/LTSEnablementStack). Essentially it's the kernel and X.org of the current release backported to the LTS release, so you don't miss out on new hardware support while getting all the bug fixes and stability that come from the LTS.
That being said, however, I'm finding 12.04 to be extremely buggy when you're using Unity+Compiz.