Ranking system possible combo?

So lets start off by saying I love the 1-50 system. I played Halo 3 so much I had to get a new disc. Reach… not so much. Reach to me didn’t feel competitive enough because an scrub with time on their hands could get to Inheritor ranking. Will they bring back to the 1-50 ranking system? No thats the simple answer; heres why I think it won’t happen.

1.) Challenges. Thats a huge innovation, it gives you incentive to do these things which are sometimes easy but are also sometimes hard.
2.) Armoury. Lets face the facts Halo 3’s armour unlock system worked really well! When we only had a few armour pices to choose from. If the armoury is like Reaches (Which I assume it will be; if anything we might get double the items[and every DLC gives us more armour make it happen 343}) so the credit system makes much more sense.
3.) Way to encourage casuals to play. Not everyone is hardcore Halo palyers. Most people are casuals so Reaches system is definaly casual friendly.

What I propose.
1.)Have a combonation of the system; best to both worlds if you will. Have it so that every playlist has a 1-50 ranking system. And lets say at level 1 if you win you get have a 5% chance to get a bonus 20k credits from the slot machine once a a day. But if your level 50 you have a 45% chance. Now of course you could have it so that way higher levels also earn more credits for winning etc. This would definately put in a huge incentive to win, making this more competitive.

2.) Have a sperate ranked playlist. But have it so that way only certain levels can enter. You earn no credits but by leveling up in the 1-50 system you unlock cosmetic armour. You have an incentive to rank up and the armour also has to be the best looking and hardest armour to obtain in the game.

3.) Have only the 1-50 system but for winning you still obtain credits to unlock armoury gear. Then just have the “Ranked” and “Social” playlists from Halo 3.

Which one do you prefer?