Well? ^^
I think I'm about at the level where I'm able to make an RPG similar to NES Final Fantasy (or more Flash-related example, MARDEK). The thing is that I have too much ideas for games, not only RPGs, and it's difficult for me to focus on one thing, especially if I'm supposed to be in charge of everything...
...alright, I still spend most of the time dragging blocks in DM. But with something as huge as RPG the major part will be story/settings etc. rather than logic itself. And to be honest, I wouldn't like to be alone with that, especially since more people are more likely to come up with greater variety of NPCs, side dialogues etc.
Of course, I can't make 10 RPGs at the same time, so if many people will want me to help with their RPG ideas, I'll need to choose. In such case I'll choose the author I'd like to work with the most. It also means that the idea needs to catch my interest.
Also, you don't need to be afraid. I have no intention of stealing your ideas. If I don't accept your proposition, it means that it wasn't interesting enough for me, anyway, and I don't expect you to give me all the scenario at once.

If you don't include all details of the game I'd like to know, I'll probably ask about them, anyway. Which might be actually a good sign, since it means that project interested me enough to ask about more.
What I might find appealing: - Original general story, plot twists, interesting and deep characters etc. (especially when it comes to unexpectedly good, yet convincing endings)
- Some sort of freedom; maybe not necessarily something which leads to multitude of endings, but if the game allows player to search for things in different orders or if there are many subquests, then it's much more entertaining.
- Humorous plot/ideas/NPCs (just note that "humour" is much wider term than "silliness", and can be played in variety of ways and situations, scary and serious including)
- Example dialogues! Or rather, I'd really like to see a kind of dialogue the author can write, and it's up to author to choose which situation they would like to show; it might be the beginning, ending, something inbetween, or even some unrelated to plot NPC. Generally, that's exactly where I'd like you to show the best you've got, or at least something close enough! (while it probably still will be little compared to the all dialogues which would be needed for such game, so there's no way I'd base my hypothetical stolen-idea RPG on that, is there?

)
- If you happen to be an artist, you can also show me example graphics of yours; they can be sprites or backgrounds, as well as speaking character portraits. Actually, an idea which doesn't require much more than bunch of simple geometrical shapes might work too.

Just note that pixel graphics don't have to be bad, and complex graphics don't have to be good (character drawings from Lethal RPG Destiny were just... ugh! >.<). Graphical skills aren't necessary, but if artist can be already found, then it's even better.

- I also like when something seemingly evil turns out to be ok in general. For example, undead creatures don't have to be as evil as they're thought to be.
- Interesting game mechanics. I don't really know what people might consider as such, but there are probably quite many not-so-overused models of RPG games.

- Interesting class/character features. For example, warrior skills would require pressing keys at proper time, while wizard would need the proper spell typed in; alchemist in turn would be able to mix items during battle to make something really explosive. It's just an example, you don't need to follow it, especially since it might take some time to code.
What is likely to repel me: - Poor dialogue/language. It's, like, the essential part of RPGs, so it should be great!
- Horribly typical stories, but I hope I won't see many of them.

- Usage of some common graphic libraries. Really, I'd prefer much more using original drawings, even if they wouldn't be of top quality, rather than something which can be seen in many other games. I particularly think of certain red-haired guy from RPG Maker...
So yes, if you don't have something original to show, just don't do it. If the idea really is that great, I guess it won't hurt to search for an actual artist (or artists, if e.g. one would specialize in character portraits, and the other one in sprites, or something).
- Detailed description of mechanics, with different formulas and such. Really, that should better be left for game creation itself, I don't need them right now.
- Same goes for characters/classes. Although I would like to read a bit about warriors, wizards or alchemists, I'm not really impressed when I see, like, 14 classes/characters, which aren't really that different. You really need to show me something unique about each of these which makes them sensible and irreplaceable party member.
Other comments: - This game doesn't have to include advanced combat/character leveling system. In fact, getting rid of levels and have battles in more puzzle-ish and less random fashion might remove the problem of grinding. You might actually get rid of battles at all and focus more on adventure aspect of game, with each quest being separate story in a way, rather than yet another "kill 50 rats" or "bring me 20 flowers".
(of course, I strongly encourage to be creative about quests in combat-based RPGs as well! Such kinds of quests as named above are actually what would be horribly uninteresting to me >.<)
What I can offer: - A dialogue system, whose recent version can be found here:
[LINK]. Not only that, but since this system is easily expandable, I can include there e.g. control of camera or character movement.
- Tile-based movement. This one should be actually much easier than aforementioned system, especially with 2D Arrays blocks I made before. ^^'
- Interaction with NPCs/devices, as well as script triggering (when character steps onto certain field, that is). Not only simple talking, but if needed, I can add e.g. using selected items on NPC as well (which might be particularly useful in more adventure-based RPGs)!
- If needed (haha, I guess it'll end up so, anyway), advanced battle system, with possible dialogues between opponent and characters, as well as possibility of making quite complex AI.
- Some help with story/dialogues/other thingies.
That's it for now, any questions? O.o'