It sounds like you'd really prefer a more innovative rating tool if you can come up with a good one, but you haven't found a model that captures what your product does.
Here's one method I've found effective for generating ideas in this type of situation:
- Make a list of verbs for the action your users will be taking -- and use words that reflect the user's state of mind about the action, not yours. I don't know the specifics of your project, but I'm guessing this could be something like "share," "promote," "show to other people," etc.
- Look up those verbs in a thesaurus and see if any synonyms express the concept you want in an appropriate way. For example, from "promote" I found the following: push, hype, boost, plug, show, and recommend.
- Use those words as the starting point in your search an effective icon.
That said, often there is merit in using an existing model. If your social rating feature is functionally identical to Facebook or Reddit in how the rating affects the product's behavior, then matching those models might result in greater conversions. (Even if it seems kind of boring from a UX perspective.)
On the other hand, if your project's ratings system causes behavior that users aren't expecting, an appealing and innovative rating model might indeed be more effective. And conversely, duplicating an existing model might actually make your users unhappy if your product behaves in a way they aren't expecting. Unless that unexpected behavior is unquestionably fantastic, like finding a basket of money on your porch.
Regarding the icons at the bottom of your post, I think you're asking the wrong question. It's easy to make a case that every one of those images can mean "vote," but I suspect that the definition of "vote" isn't what matters here. The purpose of that icon is to induce users to press it with a reasonable expectation of the outcome, so that outcome is what you want the icon to suggest. And the way to find out what those icons mean is to ask some typical users.
You can actually do this pretty easily: create four mocks (or screenshots) of the product -- one with each icon. Find someone who is like a typical user, explain a little bit about your app, let him look at one of the mocks for a minute, and then ask what he thinks will happen when that button is pressed. (Generally it's best to only test one icon with each user, because seeing a second mock with a different icon may bias their opinion.) Also, take care not to tell the "answer" when you're initially describing the product -- just give him the amount of background that a legitimate user would have when using the product for the first time.
Finally, here are my personal opinions on what those icons mean to me -- though I may not be representative of your users:
- checks and checkboxes mean "something has been accomplished" (like on a to-do list) or "I choose this to the exclusion of all else" (like on an election ballot)
- thumbs-ups mean "like." I think Facebook has made that connection too strong for that meaning to go away anytime soon.
- carat-like arrows mean either "give this a point that will cause it to be more visible to others" or "this area of the UI can be collapsed (hidden)"
Whichever icon you choose, I recommend doing some of the above testing to make sure that users are interpreting it the way you expect. (This is especially true if the rating component is a fundamental aspect of the product.)