I like the randomness that pops add and the popping sound - defines what pinball is for me. That does not mean every game needs them. I loved No Fear and JD when I owned them. However, they are kind of wasted when just used at the top of the playfield without adding any randomness (like in SM for example).
One of the things that attracts me to pinball is the element of randomness - you cannot just memorize patterns & levels like in some video games. Pop bumpers and slings add to that element but other things like magnets and spinning disks work too. Bottom line is that not every game needs pops.
TZ even tried no bat flippers (Power playfield) which many people hate but I love it. Would not, however, be fun if used on every game or in place of every traditional bat flipper.