Hmmm... The Matsuno brothers types could be-
Osomastu: ESTP He displays heavy Se as well as Fe(a bit more weaker though). His Se is shown through his indulgence on Se related activities (pornography, drinking) although not exactly 'healthy' per se. So I'm guessing either he's the stereotypical ESTP that could still use some development or perhaps an unhealthy ENxJ (perhaps an ENFJ with the Fe and all). Speaking of Fe, it is shown through his 'apathetic' overall appeal and then his subtle care for his brothers. He's not unfeeling, though. Just a 'live and let live' attitude (combined with his Se).
Karamatsu: ENFP (that wants to be a xSTP) I know, I know. A lot of people thinks he's an ESxP but, I disagree. He displays heavy Ne-Fi through his idealism. He wants to be a xSTP due to his weak Si beliefs that's how he should be along with his Fi use of wanting to be recognized. Also, through Ne, he creates lengthy poetry on the spot as well as making important (yet, often ignored) notes (ex. the Totoko Fish episode where he suggested that the problem is within the fish gag itself). A lot of people say that he can't be because he uses Fe but I think that is different. He is acting this way because of his morals. He's pleasing others, mostly his brothers (heh, that rhymed), because he thinks it is right. Also, as much as he tries to change himself, he is very sincere and authentic, much like an Fi-user. Fe-users are 'people-pleasers' and will usually repress their emotions over others. Karamatsu doesn't repress his emotions but, instead, uses them to help others.
Choromatsu: ISFJ I don't see how he could not be one (other than ISTJ). He displays big Si of how things should be and how he should do it. He's also concerned how others see him as well through Fe. He's a big guardian of tradition (as the ISFJ is known for). Also, his otaku love is mostly Ne and he displays through merchandise with sensory means. Yeah, I agree with Daybreak on this type.
Ichimatsu: INFP An emo one. I guess I could see a bit of ISTJ as well but not much. He really does indulge on his Fi of being lonely and wanting to be recognized but also staying independent and doing his own thing. There is his also subtle care for his brothers too. His use of Te is just through harsh words and contact. Other than that, he's pretty lazy. So that doesn't strike me as an ISTJ (unless there are lazy ISTJs out there).
Jyushimatsu: ESFP I can see why some people would make him an ENFP with all the random things he does but, I don't think that makes him one. He strikes me more as an ESFP for he lives in the moment. He may pull random moments and actions but that's through his Se, his taste for new experiences. Yet, despite that, there is his one and only interest which is baseball. I think that is where his weak Ni comes in for he has only one hobby that he sticks to (although, I've always figured ESFPs would have many hobbies as they search for more and more sensory activities). There is also his Fi. He's pretty aware of his own emotions but not exactly others and yet, he does try to make them happy as much as he can, even if a bit clumsily.
Todomatsu: ESFJ I think we all knew that one. He's a mischievous, manipulative ESFJ. He's considered about his status via Fe and Si, as most ESFJs are. Because of that, he's pretty embarrassed by his brothers that constantly ruin things for him (like that one episode where he worked part-time with two pretty girls). And yet, there is his care for them which he doesn't show that often (probably due to embarrassment). Also, with Si, he engages in simple, yet fashionable, sensory pleasures. It combines with his Ne as he is on the search for the new and chic ideas. That combined with Si can look like Se.
So in short, Osomatsu is an ESTP, Karamatsu an ENFP, Choromatsu an ISFJ, Ichimatsu an INFP, Jyushimatsu an ESFP, and Todomatsu an ESFJ.
