Bear in mind that Splatoon's initial push from Nintendo wasn't terribly strong either. That only changed once they got such overwhelmingly-positive feedback from its E3 appearance that they chose to really put more "oomph" into the product and gave it a bigger marketing push. With a nebulous "spring" release, ARMS doesn't have the same amount of time to pull that sort of about-face but if people on the show floor responded well to it, I'm sure they'll try more to get it out to the public. Plus it's a brand new IP in the same "simple to pick up, deep enough to invest time in" vein that made games like Smash Bros and Splatoon so good in the first place.
Much like Splatoon before it, for me this has really sprung up as a surprisingly intriguing game to come out of this conference. Seemed wacky and simple at first glance, but after re-watching the trailer and seeing more gameplay video and impressions I'm feeling an odd sense of excitement about it that I never expected. I really hope that there's a good amount of content to the package and some sort of single-player content that goes beyond simply Vs. CPU matches, because the base that they're laying down to start with is pretty cool. It's one of those "games you never knew you wanted" sort of deals. If I never get the Joy Mech Fight reboot I dream of, I'll take this as an acceptable compromise.
Also, I for one actually really dig the one-word name and strikingly simple logo that ARMS has going for it. It's silly, but punchy (pun not intended) and easily-memorable. Plus off the top of my head I can't think of many games whose boxart features the main character getting punched right in the face, so it has that going for it too.
