Incentive for winning a game - extra points such as an extra +50. Currently none exist which does not incentivize pushing for a win.
Rewards based on in game actions - remember getting a cool armor for splattering 200 people with a ghost? It was cool! Reward us for doing hard and challenging things. Especially when a weekly challenge is done, it gives us something to do.
I could ask for more. But let’s start there.
That is all 
Not just you, but tons of other players have asked for these changes as well and supposedly 343 is finally working on it but I’ll believe that when I see it, 343 has a bad habit of over promising and under delivering.
I’m thinking more as something that can be changed with a simple update. When infinite first launched, people complained about the lack of progression once challenges were complete. Next update we got +50 for finishing a game. My first point should be that simple.
My second point is slightly harder, but still an update-able change. Not saying get rid of micro transactions or progression based awards either! Keep them, it’s the way the industry makes money. But give us something to work for. It used to be fun to grind it out and then show off your hard work.