Something like Rin by Satoru Kannagi? Not just smut, but with a good plot too.

I've only ever read a few chapters of "Rin!" so I'm not exactly sure if these are similar to it but they have pretty good plots and multiple guys fighting over the uke.

Hana wa Saku ka - http://www.mangaupdates.com/series.html?id=37919
Toshishita no Ryuugi - http://www.mangaupdates.com/series.html?id=41430
G-Senjou no Neko - http://www.mangaupdates.com/series.html?id=821
Abiru Junjou - http://www.mangaupdates.com/series.html?id=1295

Yell! - http://www.mangaupdates.com/series.html?id=128
The competition really isn't anything though because it's just a bunch of guys who like the uke and try to protect him while the seme comes by and steals him away.

Remembrance, a forsaken thing that revokes ignorance and leaves people in doubt, is my only redemption and solace deep within the cascade of white.

The evergreen trees speak of days long past when music mingled with the wind and sweet murmurs brushed our cheeks.

Rin was more of a light yaoi manga series.

I definitely enjoyed and would recommend these yaoi titles:
Totally Captivated: http://www.mangaupdates.com/series.html?id=13353
Close the Last Door: http://www.mangaupdates.com/series.html?id=4030
Yasashii Kankei: http://www.mangaupdates.com/series.html?id=1719
Renai Kyoutei Nukegake Nashi!: http://www.mangaupdates.com/series.html?id=1594
Sigh's Kiss: http://www.mangaupdates.com/series.html?id=1252

(more dramatic ones 🙂
When A Man Loves a Man: http://www.mangaupdates.com/series.html?id=3619
Brother x Brother: http://www.mangaupdates.com/series.html?id=1962
Afuresou na Pool: http://www.mangaupdates.com/series.html?id=5725
Netsujou: http://www.mangaupdates.com/series.html?id=2543
Higouhou Junai: http://www.mangaupdates.com/series.html?id=40642

I read these ones long ago, so I'm not 100% sure:
Scratch Marks of Love: http://www.mangaupdates.com/series.html?id=2642
Unbalance na Netsu: http://www.mangaupdates.com/series.html?id=5032
Hero Heel: http://www.mangaupdates.com/series.html?id=927

I started it a while back, but I read good reviews for it:
The Summit: http://www.mangaupdates.com/series.html?id=1519

Did you try this one? It was listed under the category recommendations for Rin!

• Rival ni Ki wo Tsukero: http://www.mangaupdates.com/series.html?id=685