Most of these are heavily counterable (and if a Grav combo is successful it should team wipe–you’re committing 2 ults). I’d say only Tyre and Blade are annoying to counter, and Tyre usually only gets one or two kills. Blade is easier to counter tho.
Spamming ults–AKA ult stacking–counters itself. We don’t need rez for that.