There are a few plugins I can think of that I would be interested in buying if they were developed which I haven’t seen anywhere else.

There is definitely this one plugin I would like to see more than any other plugin though:

Extra loop parameters.

You know how you can manipulate loops either by your activity shortcode plugin or by the loop php files https://codex.buddypress.org/developer/loops-reference/the-activity-stream-loop/

There are 3 extra parameters/functions I can think of that I would like to see bundled into one plugin, I think they would be a great addition to the already available Buddypress parameters. They are:

1. order activities by most favorited, for activities to be ordered my most favorited to the least favorited. something like:
( bp_has_activities( bp_ajax_querystring( 'activity' ) . '&include=' . mostfavorited() . ' ) )

2. order activity by the last specified amount of hours, this is so you can combine this with most favorited, something like this:
( bp_has_activities( bp_ajax_querystring( 'activity' ) . '&include=' . mostfavorited( '86400' ) . '&max5' ) ) to display the top 5 most favorited activities in the last 24 hours (86400 seconds) – this would act like the top trending posts.

3. the type=popular parameter to work with the buddypress followers plugin. Buddypress allows parameter type=popular to order members by most amount of friends, but some of us prefer the followers plugin by r-a-y, the (github master version), however, the type=popular parameter only works for the friends component, the followers plugin doesn’t have an equivalent. This has been a feature request to r-a-y on a few occasions, see here https://wordpress.org/support/topic/order-by-follow-popularity and here https://wordpress.org/support/topic/feature-request-typepopular But it seems to be too much work for him to do at the moment.

That would complete the parameter list for me. Not sure what you think about this idea but I would love to see this.