I think you're on the right track. If anything, I would recommend reading chapters more than once, perhaps out loud the second time after you have a good sense of the meaning. This should allow you to move through the Latin more quickly while absorbing the language's structures and grammar. Heck, read the chapter three times if you need to. I think transcribing is a great idea, as it forces you to deal with every word and sentence and not miss any details.
You aren't the first to notice that LL2 is significantly more difficult that LL1. Part of the reason is that Orberg is more determined to adapt authentic Latin texts rather than write them himself, so you are often dealing with new forms of expression (which vary from author to author). For example, it takes time to get used to Vergil if you've been reading Livy, and vice versa. Also, the payoff of mastering the material in LL2 is huge. Whereas LL1 will get you comfortable with basic Latin, by the end of LL2 you are essentially reading original Latin texts from the likes of Cicero.
In other words, you can make progress fairly quickly through the more basic material, but getting comfortable reading Latin texts takes a lot more time and practice. As you progress, you need to spend increasing amounts of time to make smaller gains--this is the basic issue with gaining mastery in something. For example, there might not be a large difference in performance between a "good" violinist and a "world-class" one, but they say that it takes many, many more hours of practice to move from good to excellent.
I am a strong believer in the need to get as much exposure as possible. Even if you understand all of the words and grammar, it takes a while until you've internalized grammatical and syntactical structures. Latin sentence/clause structures and modes of expression are something that you just need to get used to through repeated exposure and practice. Then, rather than sorting through all the possible meanings and cases of a word, you will be able to interpret it quickly given the context of the sentence it occurs in.
In my case, I had a pretty good grounding in Latin by the time I finished my undergraduate studies. I had studied it for a few years and could get through Cicero and other texts, but with difficulty. While I was working a job afterwards, I had a one hour bus commute each way. I spent this time reading Latin (usually some philosophical text of Cicero). I would also often reread chapters. After a few months my reading speed and comprehension had increased noticeably (at least with regard to the authors in question). There was never a single "aha" moment when my abilities jumped ahead--it was a slow increase over time.
Horae quidem cedunt et dies et menses et anni, nec praeteritum tempus umquam revertitur nec quid sequatur sciri potest. Quod cuique temporis ad vivendum datur, eo debet esse contentus. --Cicero, De Senectute