For other busy marketplace boards such as Digital goods, I'd like to wait a while and see how this goes, but they are possible later additions.
The digital goods subs, and to a lessor extent, the service sub, generally have a target audience who are not forum members, or are less active forum members. I would suspect many of these businesses have very few, if any customers who can bump their thread.
The service announcement and the altcoin subs listed in the OP have businesses that are likely to have a wide range of forum members, and they should have customers who have the merit and activity to bump these threads.
You're right. I think that the auto-stabilization property I described actually is desirable, though, so I changed the system to provide it. Now your super-bump power is: b*(1-0.15*s/b), where b is your base power and s is the total bump score you've contributed via superbumps over the last 30 days. This gives the same result as the previous algorithm except when any 30-day period overlaps with another.
I simplified your formula to as follows:
b*[0.85^(s/b)]
I am fairly confident the above is the intention, but have no way of testing if it is implemented because I have superbumped threads in the past 30 days. If the 's/b' is an exponent, I can rule out the '0.15' from being the base because if someone has never superbumped any threads, the exponent will be zero, and the parenthesis would be simplified to '1-1', or zero, and if the 0.15 is multiplied by 's/b' the rolling 30 day cumulative superbump score (assuming 1 superbump per day) varies a lot for the first 90 days after the first 30 days of superbumping. Using an exponent to 0.85 results in the superbump power stabilizing within 60 days if someone superbumps one thread per day.
I have charted both the above exponent formula, and 0.15 being multiplied by s/b below:
b*[0.85^(s/b)]
0.15 being multiplied by 's/b':
I have also charted the individual superbump power if someone bumps one thread per day based on the exponent formula:
loyceV
charted individual superbump power based on 0.15 being multipled by s/b.
I have uploaded the underlying data to a google docs
spreadsheet.
I am still experimenting, but my current hypothesis is that the multiplication formula can be gamed by stopping superbumping for several days when the superbump value gets very low, while the exponent formula stabilizes quickly enough so that this strategy of gaming will not work.
IMO, the 30 day cumulative superbump score is more significant than the individual 30 day superbump score each day (assuming one superbump per day). The 30 day cumulative superbump score will show how easily someone can game the system by bumping many threads at once and waiting 30 days to superbump again.