How to increase newsletter campaign clicks

We're trying to grow our newsletter campaign to around 12k unique clickers by the end of Q3, and right now it looks like we’re gonna fall short.

Some context:

• List size is ~60k subs
• Open rate is ~28%
• Click rate per send hovers around 3.9%
• Clicks per unique open is ~13–14%
• Unsubscribes are rising a bit faster than we’d like

Here’s what we’ve already tried:

1. Sent a bonus edition (got some extra clicks, but not enough to move the needle).
2. Ran Google + Meta ads (limited results, only a handful of new subscribers/clickers).
3. Cross-promoted with other newsletters (steady, but too slow).
4. Tweaked the intro drip campaign by making early emails more clickable.
5. Added alternative signup paths like giving away content in exchange for joining.

I’d love to hear from anyone who’s actually scaled newsletter clicks at this level. What worked for you? What totally flopped? Any best practices or creative tactics worth testing would be hugely appreciated.