I not usually one to dredge up a dead topic (especially a topic as unpopular as this one seems to be) but recently I've been reading a lot of fics revolving around Ranma and Ryouga finally becoming real friends. It made me want to reread the manga again as a comparison.
I've been thinking a lot about Ryouga's characteristics lately so I can get an accurate depiction of his personality. In most fic's Ryouga is written as 1) A sad wandering loser who has an adorable and naive crush on Akane, 2) A miner annoyance for Ranma and co and a complete idiot, or 3) The scum of the Earth.
Now in truth, he probably has elements of all three but they seem to differ immensely depending on what arc he's in and I can never seem to get a coherent grasp of who he really is. I've also noticed that in the beginning, Ryouga seemed like a really serious no nonsense kind of guy (similar to Ryuu Cummon) but as the story goes on he starts to have these goofy quarks and ridiculously shy moments in where he becomes a gullible moron. There are times where he can be selfless like in the Ryugenzawa arc and in the OVA where he trained Akane to fight the Tendo sisters but then there are times when he's completely selfish like the Koi Rod arc and what not.
There are a few things I may have down about his canon personality but I guess I just need some extra opinions to see if they seem coherent to the canon. (and I guess this may cover some of the stuff from the old "Is Ryouga despicable" thread but it's more about nailing down his character then anything)
I truly believe that Ryouga is a very good natured guy who's just really naive and gullible for the most part. In fact, on average (or when talking to strangers,) Ryouga actually comes across as a nicer person then Ranma does because he's less likely to sound arrogant or make rude side comments (not that he hasn't, he's just less likely to do so). He's actually a lot like Akane in that respect (when involving other people) But add Ranma and Akane into the mix and suddenly Ryouga shows his ugly side: the side that's blindly vengeful and completely irrational.
However, even when Ryouga seems to be at his worst, there still seems to be some part of me that feels badly for the guy (even if only slightly). Like in the Koi Rod arc, there is no question what he did was horrible but I don't think Ryouga intended on having sex with Akane when he used it. In fact, I don't think Ryouga even has the brain capacity to think about sex at all. He's such a simple idiot that all he probably thought about was how happy in love they would be, like some fairytale ending. And when he tried to kill Ranma-chan after the Koi Mark was affecting her, he realized he couldn't do it. Even though he knew it was just Ranma, his most hated enemy, he still couldn't kill him defenseless in a dirt hole. Now granted, just because he doesn't have the intention of being/doing evil doesn't make what he does any better, but I can't see him as a despicable character either. In my opinion, a displace character is someone who intends on doing the worst thing possible and then carries it out.
Anyway, maybe I'm giving him too much credit, maybe he's more of a despicable character then I realize but I always feel that whatever Ryouga does, there always seems to be some leeway of forgiveness. Perhaps even Rumiko felt that way and hence Akari (the seemingly perfect match for him) was created.
So that's my assessment so far and I don't feel that it's much of one considering that there's much more to his character then what I just wrote.