Uzumaki is one of my favorite manga. I can't really provide a synopsis without ruining it, so I'll just say it's about spirals. It is a "horror" manga so I was very skeptical at first, but I really like the series. It is pretty short and seemingly disjointed at first, but eventually everything ties together nicely. I also thought the ending was pretty chilling. The surreal feeling to the entire work is what I enjoy the most, as well as the "what the hell could possibly happen next" factor.
HxH is one of my favorite "battle" manga ever. The premise is that there are people called "Hunters" who have special privileges to do whatever they like. The protagonist, Gon, wants to become one to find his father, Gin. While it starts off kind of boring (imo), it really picks up and becomes interesting. My favorite part is how organized and sensible the power system is while still retaining a lot of flexibility as to what is possible. The Chimera Ants arc is also too long imo and I don't like most of the later chapters, but I hope if/when HxH resumes regular publication quality will pick back up.
Ruroni Kenshin is another favorite of mine. Swordsmen like 10 years after a big war in Japan which caused a regime change. Himura Kenshin was a warrior who fought for the new government and is now a wandering samurai after being widely considered "the best." What I am most in love with is the depth of the characters, the hidden motivations and sketchy pasts. Kenshin is a very complicated, torn-up character but you don't even realize exactly how much until WAY later. Sanosuke, Saitou, basically anyone has more than one fight in the series. Hell, even some of the one-off baddies have a cool backstory and motivation. I also like that the villains, while portrayed as "evil," are still very human and can be sympathized with. The fact that the fight scenes are bitching cool is great too.
Again, it's all about the characters. Bakuman's characters are unexpectedly deep for the subject matter of "making manga." The protagonists are relatively bland, but who cares about them! Actually, only Akito is bland. Mashiro's struggle against time to make his dreams come true is very touching and the other manga-ka are all super interesting imo and well developed. Warning, it's very dialogue-heavy and there aren't many scenes with fighting, but it is a really cool series anyways imo.
Kid can see spirits and competes to become the shaman of the "Great Spirit," which is god, basically. This one is great up until the end. The characters are all interesting and the plot actually has an ending that makes sense. I don't like the ending actually, but I think it makes a surprising amount of sense for a Shounen manga. The fights are very good too.
FMA is actually my second favorite after ruroken, and probably much better on an objective level. FMA has one of the best plots of any manga I have read in addition to great characterization. If you only read one manga from my list, make it this one! Best part is, it's completed, so you can read the whole thing at once to really appreciate it as a work [:
OP is nice because it's long and just plain fun to read. It's about a boy named Monkey D. Luffy who wants to become the Pirate King. The fight scenes kick the crap out of 90% of other manga. The sad parts are sad, the happy parts are happy, and the funny parts are funny. And the overlap is minimal. OP is just a good story told well. All of its characters are likable even if they aren't as deep as they could be. Oda is a fucking great manga-ka.
Soul-Eater is the story of a group of Technicians who use Human Weapons to fight evil. They all go to a special school to learn how to fight and everything. The fight scenes from this one are fucking cool, better than OP or Shaman King imo. The characters are cool (yeah i know i have said it a lot but............) and I especially like the dynamics between technicians weapons. The duality of everything is really interesting compared to most series where teamwork is "hold him so i can hit him harder!!!!!!!" The plot is okay, nothing special but not so bad that it detracts from the sick fights and characterization.
I used to FUCKING LOVE naruto, but not really after the Kakashi Gaiden. Ditto for Bleach and the Arrancar stuff. I liked DN and YYH, but I prefer Bakuman and HxH over them and I didn't want to put more than one work per manga-ka up d: