| Bartheus |
That wouldn't work at all for people that don't actually gain martial proficiency, erasing dozens of viable concepts as basic as a martial bard.
What could be a viable alternative solution would be to simply make it level dependent like:
Attack trait: blahblahblah. At 4th level and every 4 levels thereafter (8,12,16,20) increase your damage by 1 weapon die. (with probably some language to only make it apply to actual weapons and not spells/innates/etc)
Of course changes like these would require rebalancing which classes get weapon proficiencies and when they get them, changes are also possibly required for other subsystems like feats related to fighting. Still I personally think that if there is a martial bard, then he should have better than normal (= Trained) weapon proficiency, isn't that the point of the different ranks in proficiencies? Otherwise he isn't really martially trained beyond the basics.