When the SSD is bricked to read it's the redirection table that is corrupted. The corruption means that the random bits are wrong. Once the random bits are wrong, the redirection is wrong. If the redirection table is in the separate flash, you have to spend more flash for redirection table than for data, as that table will be heavily stressed (the redirections have to be often updated with the writes if you want good wear levelling). If you offload the part of the redirection table to the "normal flash" you're still at the beginning. Some random bits will be wrong after some write and you depend exactly on them to be able to read properly.

I would put the entire redirection table on ram, and only write it to disk (to a dedicated area) when turning off the power.

By doing that, that area will easily outlast the regular flash.

Hope you have ECC RAM :)

Also hope you never have a power outage or hard reset of any kind.

ECC RAM? Easy.

And as for power outages and hard resets, there's these nifty things known as capacitors. It only needs to last as long as is necessary to write the data to flash.

A better option would be to spend lots of time repetitively writing down the pointers in newer and newer iterations every N blocks, so that of fallback available if one block holding pointers fails.