If you're main focus is to mostly receive 1-2 video streams while sending 0, then, yeah, I guess bundle vs non-bundle doesn't matter much. I'm pleasantly surprised to hear that 25 PeerConnections work well for you.

About simulcast: why would a sender not support simulcast? Something to do with VP8 hardware encoders?

I'm still interested to hear what you have learned about AQM and the like.