Here’s my take:
Most F2P games use daily missions as a way to encourage players to come back every day and to moderate income generation. They want to ensure both casual and dedicated players get enough income that the game feels fair (i.e. not pay-to-win) but not so much as to discourage players from spending real money.
I would like to DB try to adopt a similar system for its daily missions. Either a set of 3 missions each day or 1 mission that resets every 3 hours would be a lot more reasonable. Missions should be relatively token tasks like “Play X matches of [mode]”, “Earn X experience with [merc] in your squad”, or “Earn X [combat/non-combat] experience” (I dislike game-mode experience as its own quest because it is earned so unevenly across the maps).
To compensate for making missions more bland and less frequent, new types of missions could be created. I would love to see one-time only training missions, with a few becoming available each time you level up until level 10. A daily challenge with a modest credit reward could be a fun diversion for those so inclined (example: “As Fletcher, kill X players you have stuck”). Finally, long term quests every now and again would be a welcome addition. Lasting anywhere from a week to a month, players would be tasked with completing one or more tasks that require significant play time to accomplish. For example, if the current rotation was Proxy/Sparks/Stoker the quest might be to get 100 Proximity Mine kills, 100 Revivr headshot kills, and 100 double kills with the Molotov. Quests would ideally have some sort of special reward, like mid-tier case(s) or even a cosmetic for special events.