Finally gave up googling and decided to just ask people with real experience.
The free tiers on most of what I've tried are basically useless — you get just enough to see that real people are there, then hit a wall the second you try to actually message anyone.
What bothers me most is how hard it is to find real, unfiltered opinions. Forums like this are honestly more useful than any best-of list I've found through searching.
If you've got experience with any platforms or approaches that work, drop them below.