I think all of these are solid ideas but ultimately very boring. That's what I like about bits for boops, it's at least an interesting look at the problem and an attempt at a novel solution. I think hubski should lean on their lack of funding and not force a revenue model so long as they don't really need one, and based on the fact that they aren't begging, they don't seem to need one.
That said, I think taking apart the problem can help a bit with finding that more novel solution. So...
Until yesterday Hubski had one kind of capital - social. Everyone got one vote per comment or post which they could always choose not to use. Yesterday mk introduced that sweet, sweet bit capital and those are the two I want to focus on.
The goal, as I see it, is to create a mechanism that turns social capital into bit, or financial, capital but doesn't allow bit capital to become social capital. That is, hubski and its community should be paid for their contributions, but shouldn't be required to pay to contribute.
There are two parts to that puzzle, getting the bit capital and distributing it. The easiest way to get our bit capital is through advertising, though this doesn't adhere to the second part of our mechanism as we're allowing individuals to buy access to the community (social capital) for bit capital. The gated content model has similar problems but instead of posting a message to the audience in exchange for bit capital, you're just allowing access to the audience in general for bits. In some ways this is better, but in some ways (to me) it's worse.
Your value add model is an interesting one and it's worked successfully in games for quite some time. The basic gist to the video game version is to open the platform as a simple, but complete, space where you gain access to more functionality through time. You can bypass the time restrictions through money. Take Team Fortress 2 for example. All of the weapons in the game that have effect on actual game play can be unlocked through actual game play, or you can spend a few bucks and buy the weapons now. Such a system could easily apply to hubski where you earn gold tokens through the slow acclimation of social capital, or you can buy them in bulk with bit capital. This is one of the more interesting systems for me, but creating such a system would take a lot of time and consideration.
Getting back to the puzzle, I think this bits platform offers an interesting foundation for the solution to the problem but ultimately seems to come a little short. While it's a solid way to move capital around the site, it feels like it bonds the social and financial capitals too tightly to one another. My suggestions all revolve around putting a bit more distance between the two. If, for example, you had bits you would suddenly see a golden hubwheel next to the blue one. A vote on the golden wheel notches up the blue but also adds bits. A vote on the blue acts as regular. Similar mechanic but more granular control.
The other idea is a social marketplace. Every week, month, quarter, whatever, the doors of the social market are shuttered and can be opened again after a minimal contribution. This might not be necessary but in this thought experiment offers the initial bit income. Once the market place is open, individuals can ask for social favors in return for bit capital. For example - if I wanted to host a story writing contest, I could offer 500 bits to the best author. If I wanted to have a cities skylines tournament, I could charge every entrant 100 bits and payout 10,000. If I wanted to see the tightrope priest less often I could start a kickstarter style bit project and get better servers once it reached 1,000,000.
There are gaping holes in this idea but I think it could build well off of the current bit exchange program. It's likely too complicated for what hubski prefers, but I like it.