Because there are just too many matches to comment on every single one of them, I will only discuss which matches will be close and/or which matches will be pivotal in terms of how the final round will look like:
Arena 4: More likely than not, the final match up here will be a KamiNomi final between Haqua du Lot Herminium and Takahara Ayumi. I say this because KamiNomi fans would love to use this bracket to their advantage such that Haqua can get a clean ticket to Regular Season. While Haqua is seen as the ultimate victor, if Yarizui Sen can somehow manage to break away from the double vote and move on, she will at least give Haqua a much tougher time to win that someone of her same series. Sen should be stronger than Ayumi, but, looking at how they are placed, things might go either way.
Arena 9: This will be a very interesting match to observe. Guilty Crown is still following through from the final episode boost, and with enough momentum, Tsumugi has a chance to defeat Hakamada Hinata. In the event that Hinata does win against Tsumugi, which I think will happen, it would be a rematch between her and Sakura Kyōko. This will allow Kyouko to get an easier victory to Regular Season, since she has already defeated her before. If Tsugumi wins, and Kyouko does not do a good job at defeating Oshimizu Nako, who should be weak, I am to expect that this match would be very close. Tsugumi migh actually defeat Kyouko if she puts her guard down, so those who would want Kyouko to advance are going to have to support Hinata and hope for smooth sailing.
Arena 18: Ikaros is seen as the victor, but which of her opponents will she have to face to get that spot. If Kanzaki Kaori wins, Ikaros should be able to have some smooth sailing, but what about Saten Ruiko? To date, Ikaros has never defeated Ruiko in singles competition. While they have only shared one match in ISML, this will test how much either she or Ruiko will have what it takes after a one year haitus for both characters. Those who want Ikaros to be in again would have to vote for Kaori. However, those who want to push Ruiko again will need to do so, for she will be the one to give Ikaros a much harder time for victory than previously thought. My guess goes to Ruiko’s victory.
Arena 22: Again, nothing much to see here. Since there are two Hayate no Gotoku characters, the fanbase is most likely going to push both of them to victory then sacrifice Maria such that Sanzen’in Nagi will be able to walk into Regular Season with ease. Those who do not wish to see Nagi in ISML anymore would have to vote for Lucy Heartfilia for victory. Now, Lucy’s popularity is quite questionable. They seem to be the only Shounen Jump series that actually has what it takes to go far, unlike their other brethrens like Bleach’s Rukia. While Maria looks to be the victor in this arena, with enough of a push, Lucy can get it and attempt to give Nagi a run for her money, however impossible it may seem.