I didn't have a chance to play Smash Run. But I'll put it like this: comparing Smash Tour to Mario Party is unfair. To Mario Party. It is "Random Crap Happens And Someone Is Declared The Winner" to a ridiculous degree.
Characters are dropped onto the map such that you know who's going to get them as soon as they appear. Yup, some jackoff is going to get your favorite character while the RNG decides Jigglypuff and Marth are perfect for you.
When fights happen, you might just die at the word go, because while you're busy soaking in that you're Marth, the match is going to be an "Explosive Smash," and the only in-battle item you have is a back shield, the other players are using their in-battle items that make you start with 100% and give them Hammers. You'll figure out why you died...after it happens.
The last match has one cool thing about it. Each of your stocks is a different character. Why wasn't this a normal mode where you can choose your characters!? The dumb part (other than that you're probably going to be using characters no higher than #14 or so on your favorites list) is that it's time mode. Meaning, you can go in with two characters, lose them both halfway through the match, and still win if you had enough KOs.
The entire mode will make you feel young again. In the worst ****ing ways possible. You have no power in it. Decisions are constantly being made for you. Something bad will happen, it won't be your fault, but you'll be punished anyway. The other players will get things you want. You'll be stuck with things you don't. You will want to cry and scream, "this isn't fair."