Hm...I didn't know SSMTs were given a one word moniker...
I snake.
I'm curious as to how you'd disable snaking, but not MTs.  Unless you give the option to completely disable MTs.  Which wouldn't bother me.  
I would like battle mode to have larger size arenas, like the older days.  A few more arenas, and use larger engines.  50cc (hell, it seems slower than that) makes it next to impossible to just dodge  a red shell.  You can still block easily, but dodging is another matter.  Overall, I just hate the sluggish feel of battle mode.  It's still fun, but I think faster would be more  fun.
And go back to five races per cup like the SNES.