While investigating an issue with a non-propagating transaction with @TheBlueMatt, it occurred to us that it can be a problem for a node to get its transactions relayed when it's surrounded solely by low-mempool-limit peers (which correspondingly have a high announced minfeefilter value). And it appears this is detectable too, as our own mempoolminfee would be lower.

While obviously relay can't be guaranteed, this is a detectable situation, and it could factor into the outbound replacement logic and/or trigger something similar to the "seek more peers" behavior we exhibit when we appear to be not getting blocks.