Ways to increase available stable room members

[JakeTrock]

I run a webapp at https://www.hokucode.com I use a digitalocean VM with 512 mb ram and a single-core cpu. are there any shortcuts to allow more clients per room, like possibly lowering bitrates or some other solution? (I don't use video either). Should I keep using socket.io?

p.s.
I remember an earlier post in the issue section stating that only 3 stable clients could connect at once, does that still apply?