Ya @Markus_b my response was a quick one but as you seem happy with v5 and have come to find that your 8% bump is a good result then IMO there is no need to move away from that just because there is a new version.
With filmic the norms are always a big part of the end result and with the new math in v6 they will be different as well. So you can experiment with v6 but there might not be a lot to be gained since you have a workflow with filmic already.
Filmic is designed to be used with color balance rgb and a couple of generic presets are provided for that so you could move to v6 and then try them or try to get your own preset in that module to bring back your look but again it might be more effort and to what end if an 8% bump works in v5…