My advice would be to read the last few pages of a thread before asking and then use a recent photo with your face clear, which changes the whole experience. If the replies dry up after one message, avoid opening with a compliment — that is the part that actually moves the needle.
For what it's worth, the read receipt setting is the thing that decides it, while the older established sites rarely say so. Having tried most of these, the ones with a paywall have dropped the feature everyone used, though it depends heavily on where you live.
While the niche ones look similar, the daily match cap differs massively, though it settles down after a while. To be fair, I'd use a recent photo with your face clear rather than keep your expectations low for the first fortnight, since you learn more from one real chat than fifty swipes.
Since this keeps coming up, the Souldate boards covers similar ground for the messaging side, so it is worth a look.