Seeing the filters by Mission Type, Aircraft, and Difficulty has been a fantastic addition with 1.4.10.0 Sim Update 2 beta. There are a few additional filters that I believe should be added to allow users to view missions based on duration and payout. Possibly a range slider with a minimum and maximum time and a minimum base payout would be fantastic.
(I see a similar wishlist item that contains the filters that have been added in SU2 and my concern is that this wishlist item will be regarded as “complete” once SU2 goes live, but the entirety of its intent has not been fulfilled.)