T side mode 1 msg 0 has 2 unused bytes that can be reconfigured.

Msg 5 and Msg 6 are the perfect candidate for patching. We can make msg 5 shorter with the only the data that`s displayed in the eehack and get very high refresh rates. Msg 6 is already short.

Msg 3 has all the inputs and outputs + all ad channels even the unused ones and e and t side so I think is very useful for now diagnostics and for other purposes like additional ad channel.

Msg 5 has some bytes that still have no clue what are doing.

Msg 6 is for auto transmission adapt learn values and are rarely used if at all.

Msg 2 is also not used in most of the programs I have tried it contains only dtc and some status bytes.

Lenght of the output message is defined in the fifth byte (data + checksum).
You can also reconfigure mode 2 lenght message up to 112 bytes in 16 bytes increment. Just change $41 to $51;$61 or $71 to make it longer.

Mode 0b can be hacked for something usefull. The main obstacle, there is only 28 free bytes on T-side.

Also mode 4 can be added on Eside for table switching or something else.