Discounted Bit Gifting
Once subscribed to a channel, a user will get access to the normal unlocked things but also access to a new tab next to "Gift Subs" called "Gift Bits." Gifting bits directly through a channel the viewer is subbed to will provide a discount. For example we'll say $1 = 100 bits. One option would be $1 = 110 bits if subbed...or, you could implement it as .90C = 100 bits.
You could scale bigger discounts based on longevity (consecutive months subbed) or through level of subscription (Tier 1, T2, T3.)
I do not have financial information on twitch but I imagine that the primary revenue stream is through subs/gifted subs and a supporting revenue stream of bits. This discount would encourage secondary monetary support and engagement from recurrent viewers. Providing an incentive to further support a subbed streamer will increase conversion rates for twitch and higher bit engagement for streamers.
With a volume discount theory backing this implementation, conversion rates, repeat purchases to a subbed channel, and profit margin depreciation would need to be monitored.
It could be possible to mitigate profit margin erosion through the use of a time limit ("You just subbed to x channel. You have 3 days to gift x bits for x discounted price.") This could provide both sense of urgency and increased optics that there are secondary methods to engage with a streamer.
A secondary option could be to split the profit margin erosion on the back end. The (profit margin - discounted profit margin) / 2 could be split between the streamer and Twitch. This would need to be implemented fairly and transparently as both Twitch and the streamer would receive less total payout. New bit volume would be key to sustaining this relationship.
Either way, I look forward to hearing any ideas about this!