Ok so here are my opnions on Halo 4 right now with some ideas on what to carry over to Halo 5 (xbox one). Please leave feedback but please re frame from disrespecting my opinion, its an opinion everyone has one. 
You know 343 I have to give it to ya you have done a great job with Halo recently… That said your not there yet. I love the new Legendary slayer its awesome and to be honest that should be the only slayer in Halo 4 because that is what halo slayer is! Now i can see you looking at the amount of people playing Legendary Slayer and say why bother the numbers aren’t there. And trust me I understand that but there are 2 things that play into why that is. 1- “Better late than ever” doesn’t work here most if not ALL of the core Halo players are gone from Halo 4 and those are the people that want Legendary Slayer the classic HALO slayer experience, there are a few hundred core players and maybe some casuals that do play Legendary but as I said that main core is gone. 2- Infinity slayer. You have Infinity Slayer now there is nothing wrong with this playlist except the fact that it isnt HALO which is a problem. Most people that play Halo’s slayer types choose Infinity Slayer and the main reason for this is that most of these players are casuals or noobies to the Halo franchise and dont know the classic Halo core feel. They arent that competitive so they might see Legendary as too hard for their liking so they go with what they like, Infinity Slayer.
So please 343 I beg you do not feel that making the LS playlist was a waist because it wasnt! Numbers are not accurate right now. The amount of ground you are making on Halo 4 is great! You are bringing that Halo feel back! But you have a ways to go so please do not go by the numbers of the playlists because those numbers are not accurate. Listen to all the people in comments on youtube and on ALL the forums that are telling you what Halo is and needs to be again.
I am extremely pleased and encouraged to know that you as a developing company of one of the best franchises in history is listening to its community and fans.
Thank you 343i for what you have fixed so far and I just hope and believe you will continue that with Halo 5 (xbox one)