It's nice that you'va been able to complete your first tasks.

I don't know how you count the operations or transactions and what's the requests you have done. Did you consider that a transaction can contain more than one operations (e. g. transfers)?

resurfacing posts in user feeds when replies are entered.

This is very interesting. I thought about something similar in my last post. The resurfacing in the user feed would be an even better idea. Just as resteems also show up in the feed.

Of course, the prerequisite is that the users pay attention on their feed.

If I post on Facebook or Twitter, it can take me a matter of seconds or minutes

But that is not necessarily the case, is it?
I think your post above wouldn't have been created faster there. And you can also create one sentence posts quickly on Steemit.
But who wants to do that?! And who wants to vote for that... except bots?!