It's a nice idea but makes no sense storywise. The marks are rewarded by the faction who you are assisting while doing certain content. Why would Omega force care that you've spent days tagging animals on New Romulus? Why would the Romulans care that you just saved Defera from the Borg for the umpteenth time?
I agree to a universal mark system that at a cost of 2-5:1 to convert will be the better way to go and should be tied into every mission that is not not themed (i.e not an adventure zone, fleet actions or stf) for the main marks that you need with at least 100 dilith to be added ontop.
Will allow people to slowly save up their marks from a secondary source when they want to take a break from grinding out the main themed marks from the events.
Hell turn Fleet Marks into the Universal Marks and you won't need to add a 4th mark into the game.