At the end of the day Rock Band 4 feels more like an evolution than a drastic departure. If you've always wanted to put your mark on a song, then the new self-expression enhancements are reason enough to give Rock Band 4 a shot. Couple that with a branching career mode, support for your old instruments and DLC and Rock Band 4 stands out as the best game in the series, even if it's missing some core features.
Phantom Pain is hands down one of the best game's I have played in a long time. The open world environment offers you an endless amount of ways to play. Phantom Pain is a game you can sink over 100 hours into and still come back for more. Even if you haven't played past Metal Gear games, Phantom Pain is a great place to start.