With the network topology changes and after Ethernet switches upgrades I miss more and more support for any way of the Ethernet ring protocol.
It will be nice if the software bridge will be capable cooperate with some ring protocol, probably best with ERPS /ITU G.8032v2/, which is supported many IT/telco switches (a MRP protocol /IEC 62439-2/ is mostly domain of the industrial Ethernet devices but we use it in few places too).
The shorter L2 recovery time is usefull to keep too short L3 recovery time when there is any L3 service on the top of this ring - like VRRP or OSPF/BGP with active BFD.

A customers do not want to wait 4 seconds for fail over with the RSTP dinosaurs when there is ~100 milliseconds solution for simple ring network!

How bad is RSTP in a ring?

On small ring (3-4 switches) can have RSTP similar recovery time in comparison with ERPS. But with larger rings have ERPS recovery time still around 50-100 ms and RSTP around 4 seconds and with large rings is this difference greater (some industrial versions of the MRP protocol have recovery time for ring of the 100 switches under 20 ms but this is not mainstream solution).
A difference is too when network is build from multiple connected large rings, for the ring protocol is still recovery time under 500 ms but for RSTP can be impossible handle this network.

There are many ring protocols but for metro/telco sector it looks that G8032v2 is now supported be large numbers of the vendors so will be nice if the Mikrotik will supports it too.
There is problem when I want make looped L2 connection between Mikrotik and network which uses rings. If there is only one ring then is not problem, usually can be used mixture of the RSTP and rings. But if there are multiple rings/subrings then only ERPS can be used.