Just bear in-mind the standard ecu parameters are set to cater for everyone, those that drive the car and do not maintain it, use cheap supermarket fuels etc. Remapping will fine tune those parameters and release the torque and power that is there but held back. Most graphs from standard will show poor AFR results so remapping will improve performance and economy. It is about tweaking the map and if any
mods have been done this can be covered and you will get the best for all conditions. How you control it is down to you, if you wish for switchable parameters due to shared driving then that'll need a custom set-up. Personally I'll look to get the
mods completed then get it mapped to suit, you will be surprised at the results and how better on fuel it would be too.