Right now clicks on Twitter ads are worth very little because most of the clicks come from fake accounts. But imagine how much clients would pay for "verified clicks" -- clicks from verified accounts.
IMO they should make their ad sales a tier-based cost-per-click model with clicks from verified accounts selling for higher amounts than clicks from non-verified accounts. If theyre smart they'll open up a third tier above "verified" for the twitter-endorsed superstars which will have prestige value again (now that the blue checkmark has none). Maybe a green checkmark would work. Naturally they could sell an ad click from a green checkmark account for even more than an ad click from a blue-checkmark regular ol' verified account.
There’s another solution: the platform is free if you have less than n followers or follow less than n users. Say n is 15 for example. Above that you pay for every tweet. On a sliding scale, say the first tweet/day is 5c, the 10th is $1. They could even ditch scammy advertising - brands who wanted to “engage” would simply pay directly to tweet.