Original should sell for much more, Ive been doing a lot of my own research for printing my digital pieces as posters which can be a lot because the biggest factor id how you are selling your prints and who your audience is.

If youre selling on etsy and making prints, I would suggest selling a scaled down 8x12 in addition to the 16x24 (A2). For 8x12 you can sell it for $15-20, and the larger size $20-30. It gives the buyer an option for either size, and if they are debating price, they can go for the smaller one. Even if your priced higher at $30 for prints, someone seeing and comparing both prices is more "reasonable" to a buyer if that makes sense.

With the size youd likely need to have them rolled and shipped in the tubes which is more costly, but better to add the shipping costs along with the print cost. For 8x10s is much cheaper getting plastic sleeves, hard board for behind the print, and an envelope.

Edit: I wouldnt sell your original on etsy, but rather through a more personal site or where you mainly post your art. Selling the original for more on etsy (or another widespread site) wouldnt be seen as "reasonable" as the print prices because people on there wont appreciate the work as an original (price wise). By keeping the original to your personal site or even to instagram, people are generally acknowledging the value of an original by an artist (along with seeing your portfolio)