After twice bringing this issue up in the PTS and also trying to contact yannick through twitter and getting no official response either way ill try yet again...
Firestarter expertise upgrade bonus needs to be changed at the moment it is "damage" this only applies to the initial explosion not to the burn this makes expertise/proficiency on this skill not worth any time/effort to raise.
For example the Burn sticky bomb gets a burn damage increase it make no sense that firestarter does not have the same bonus this needs to be fixed ASAP.
Riot Foam expertise upgrade bonus is Ensnare Health this is totally useless and also makes the skill not worth the time or effort to raise it's expertise /proficiency this skill should get an ensnare duration bonus to make it worth the effort and again should be fixed ASAP.
These 2 skills are part of my two most played and imho fun builds and i'm a little annoyed that they have both been ignored by the devs even after the issues have been pointed out by me and others during the PTS.