Ikebukuro

Pros

• if you like J-pop, K-pop and/or idol projects (or even idol-adjacent content like Hypnosis Mic), you're better off in Ikebukuro
• add ikebukuro to ur anime day I found that there was almost a better selection of good there if u wanna do shopping and less crowded :)
• If you are into anime merch it might be worth it to do Ikebukuro while you're in Tokyo.
• You could also use it to go over to Ikebukuro which has a ton of anime/nerd stuff but is a bit more chic than akihabara, so it could also be a good group destination.
• Main reasons: * major station * easy access to Shinjuku and Shibuya * close to Nakano * plenty of food and shopping nearby * easier place to come back and relax at night * better hotel value than central Shinjuku

Cons

• I also visited Ikebukuro... it is absolutely not better than Akiba, and from what I saw the prices were ever so slightly lower.
• Because it's a national holiday (Coming-of-Age Day) and Ikebukuro is a center for young people to go out, Ikebukuro would be (and will be) one of the places I'd stay away from on 11 January.