There are definitely a bunch of ways you can improve on MBT questions, but the message boards aren't necessarily the best venue for that. If you go to Office Hours, filter for my name and I've done a bunch of lessons on MBT questions that should definitely give some new insights into these questions. Of course, if you have any specific questions feel free to ask them here, or if you'd like any specific help I and all my colleagues would be more than happy to help in a 1-1 tutoring sessions. Here's a couple quick things I can tell you right now.
MBT questions are designed to be answered. Sometimes people are way too strict with their variables when diagramming, and a slight tweak to the letters they use can lead to more chains.
2: Practice S&N! I've seen hundreds of students in private tutoring, thousands through office hours and message boards, and not a single one is as good at S&N as they think they are. That isn't meant to insult, it's meant to say there's always soon to improve! My score on the LSAT only broke into the 170s when I went back to S&N basics, and drilled those flashcards every day for a YEAR. They might be worth taking another look.
