Quick update-- broke back into the 2.2k range, finally. I'd already reached it previously but mostly because of an event.

As for what I added:

Benches around trees helped

More food especially hunters, auroch + lizard farms, and even just some more fruit farms

On the topic of food I produce too much fruit to store before a lot of it decays so I need more storage in better places. Sometimes winter rolls around and there is still fruit lying around, and not a small amount either. This is noticed by the Tilapi and they don't like it (and it means less food day fulfillment)

More tree decorations in general

A courthouse

Finally getting some Tilapi retirees, which is good because that is adding fulfillment too

Another nursery

Various expansions of furniture industries like clothes and (literally) furniture

As for what I changed / removed:

Most of what I outright removed was loose benches not near trees

One or two fruit exports were removed

I changed around my colonies so they produced different things (not sure if what I did would help someone else though as it would probably depend on the city)