Mother 3 is basically improving upon everything I loved in Earthbound. There's this whole rhythm-based combat system going on that feels really good once you get it down. I might have said something about how much I love dynamic music before and I had no idea it was a feature in this game. I haven't played any real RPGs so I don't know if it's a general feature or not but the way health ticks down when you take damage is fantastic (say, if you take lethal damage, you have like 10 seconds to queue up a heal and it'll keep you alive). If you finish a battle (or flee), heath stops ticking down, so gambling on rushing down an enemy can be tense. It's all just really fun.
The games' humour is spot on and gives you more than enough reason to talk to every NPC and check every corner for all the shit the devs have thrown in for the people who'll look for it.
Mother 1 apparently sucks ass but I'll end up trudging through it after 3. Loving these games