I agree totally about the knockdowns, there are just too many and occur too frequently. I mentioned it in my sim mode question thread but it didn't get many responses unfortunately. Your point about different outcomes when the block is broken is an interesting one as it may add some much needed variety.
In a similar vein to the finish the fight sequences, I would love more variety as it helps to keep the gameplay feeling fresher and less canned or the remind you that essentially the outcomes are somewhat pre-determined