Suggestion 1: Merge bardic lore with performance for all bard abilities. Bluff, whistles, screams. They're all performing related after all, and it makes sense that performance should have a special use for bards.

Suggestion 2: Turn bardic lore into a meta skill that applies a bonus to whatever the bard is doing. The more likely to fail (difference between bardic lore and the ability) the more likely bardic lore will help boost that skill. This could come in the form of an extra save roll on failures, increased critical success chance, increased learning rate of tertiary skills (I know, wishful thinking), or a static (non-stacking) buff to all skillsets (very minor for lore, larger for weapons and survival). It could be a minor, always on buff, or it could be a stronger mojo draining buff.

Learning: Listening to non-bards teach classes or teaching non-bards classes, tertiary skill sets teach better than secondaries. Primary doesn't teach. Casting spells not in the bard's domain. This includes War Mage spells for those not interested in sorcery, but obviously sorcery would teach it well. Recalls would be a primary teaching method. When it "procs" a small amount of learning is added. Minor training when using tert skill sets or appraise focus on a tert/secondary skill.

IG reasoning: Bards are the masters of lore. Wouldn't bardic lore be about preserving that knowledge; using it to further your own needs. Let performance be about performing, and in practice give both of these skills a purpose.