This is based only on my personal experiences and interactions.
How do you feel about the changes?
In my particular case the changes have been exclusively positive -- I've gotten more attention and far more rewards than before HF20. But then I've only started one month before the fork -- was just getting the hang of things.
Will they help or hurt Steem from growing?
I don't know if it was just the anticipation of the fork or was it because HF20 was the real backbone that dApps needed, but there was a definite explosion in activity and development right after the fork. I feel like that's helping STEEM grow.
Are we in a better or worse position than Hard Fork 19?
The HF20 drew attention and made people concentrate on smaller members of the community, on newbies and strugglers. As a newbie at that time, I could say I was very fortunate.
What do you wish made it into Hard Fork 20?
Here I will just steal an old answer from a more respected and knowledgeable member of the community.