While a 30% discount is admirable for Nitro and Nitro Classic members (resulting in a $3.49 charge per month, per extra boost), I personally don't think that's cheap enough. I make a respectable income and even I would never imagine paying that much per month. So, I have one of two suggestions!
1. Decrease the monthly server boosting price. This is straightforward. Perhaps reduce it for nitro members down to $2.00 or so, and then I (and many others) would consider using it.
2. Make additional boosts a one-time purchase. With this, you could actually charge a bit more for one-time boosts. $15 per extra boost, with a 30% discount for nitro members remaining the same, at around $10 per extra boost.
Just ideas floating around in my head to make me actually use the additional server boosts. Thanks for hearing us out!