Well, UX depends greatly in the kind of game you are making. I consider the term "RPG" as a super genre (super class). In it you have WRPG's, JRPG's, Action RPG's dungeon cralwers, MMO's, etc. Depending on the the game, the concept of party and it's associated mechanics will change.
You also have to keep in mind that in some games a good UX may not be desired. While I believe an RPG's UX should be good (messing around with menus and inventory shouldn't be a chore), see the classic Resident Evil games.
One of the goals of the games is to evoke an atmosphere of uncertainty, fear and powerlessness. See how the health indicator is not a concrete value (75% life, for example) but an approximation (yellow life. You may know yellow means it's in [30-70]%, but you don't know the exact value.) This helps achieve the desired emotion while being, according to the traditional UI principles, a bad UI. It's not transparent enough for the user.
I consider the game's controls to be part of the UI. It's by using the controller and how the character moves the you interact with the game. MAny people dislike the RE's "tank-controls"[1], but I find it was a conscious and deliberate choice by the game designers to adopt this type of control. It's harder to control the character but help in achieving the desired emotions.
So, to answer you question... I don't know. But it's harder to evaluate game's UX's because it can't be evaluated in the same way we evaluate traditional UX's. Sometimes, in games, it's good to have bad UX's.
Ok, I know I've ranted a bit. First, what do you want? Just good examples, or you're thinking of making a game andwant some good examples?
Now, for inventory. You can have the party inventory, like in JRPGS or the character inventory like in Baldur's Gate. Personally I prefer the party inventory because there is a lot less fiddly. But the other kind is more "realistic". There is one game that mixed the two in a way that I enjoyed. You have a party inventory but each character has "slots" where you can put items to be used in battle. But in this case you don't have the whole inventory available.
Then you can have an unlimited inventory, like in JRPGS, or a limited one. You can limit it in two ways: Limited space like in Diablo, or limited weigth capacity like in Skyrim. In my opinion you should never mix them both. It's too fiddly, and too frustrating. In limited space you also can have item of diferent sizes. This is fun because inventory menagement becomes a sort of minigame (again, Diablo makes this pretty well).
With party control it's a lot more complicated. If the game is turn based or if there is the option to pause the action, the player should have total control of all the mambers of the party. If it's all real time, there should be an option to ssue orders. One game that does this well is Mount and Blade. You can issue orders to your troops including, IIRC, you could issue orders to the different kinds of troops. I feel this would be a nice addition to Skyrim, for example.
About status, I really liked what Final Fantasy VII did for status effects. If a character was nead death he would appear hunched, if confused he would have stars swirling around his's head and if poisoned he would glow in green. If he were under all these status effects, we would show all three effects and they didn't overlap or be in conflict with each other.
But, as I said in the previous post, it still depends on your objectives in the game. In pokemon you have direct control over your pokemons but I would like to see a similar game where you don't have direct control and you have to train their AI.
Knights of the Old Republic was fantastic in terms of party management screens. The inventory screen was rough, so some way to collapse into item categories would have been appreciated.
Skyrim isn't bad, I still don't quite like the weapons screens though. Something about them all being in a list bothers me. In a way I see why they did that, but I'm so used to going to a screen similar to KOTOR or dragon-age that doing it the KOTOR or DAO way just feels more natural.
I'm a console gamer so in my opinion the biggest problem is having controls mapped for your character, and also having to do in-game hud menu navigation, AND having some way to command party-members, though voice control can resolve some of the command pain.
hmm thats a good question. In most games like that the interface is awful.
This is not an rpg but 'frozen synapse' and 'frozen endzone' are actually good examples of a UI for controlling multiple guys acting simulataneously.
Also I remember dungeon siege having a pretty basic interface but also being quite functional (with 8 people in you party!)
The 'eye of the beholder' / 'might and magic' / 'legend of grimrock' way of doing things is effective but it basically turns your 4 characters into one big one
You also have to keep in mind that in some games a good UX may not be desired. While I believe an RPG's UX should be good (messing around with menus and inventory shouldn't be a chore), see the classic Resident Evil games.
One of the goals of the games is to evoke an atmosphere of uncertainty, fear and powerlessness. See how the health indicator is not a concrete value (75% life, for example) but an approximation (yellow life. You may know yellow means it's in [30-70]%, but you don't know the exact value.) This helps achieve the desired emotion while being, according to the traditional UI principles, a bad UI. It's not transparent enough for the user.
I consider the game's controls to be part of the UI. It's by using the controller and how the character moves the you interact with the game. MAny people dislike the RE's "tank-controls"[1], but I find it was a conscious and deliberate choice by the game designers to adopt this type of control. It's harder to control the character but help in achieving the desired emotions.
So, to answer you question... I don't know. But it's harder to evaluate game's UX's because it can't be evaluated in the same way we evaluate traditional UX's. Sometimes, in games, it's good to have bad UX's.
[1] http://tvtropes.org/pmwiki/pmwiki.php/Main/TankControls