I do what I can.
Well, he loses 3 sorcerer spells known, of which he could have had more 5th level options, as well as 6th and 7th level options. In exchange, he gains 12 bard spells, up to level 5, and 4 more 1st and 3 more 2nd level slots.
Is it too powerful? I'm honestly not sure. Are 6th level and 7th level spells worth 3-4 spells under level 5? (At best, a 9th level bard could know 2 5th level, 4 4th level, 4 3rd level, and 2 2nd level spells.) Are 9 levels of lower level features worth 5 levels of higher level features?
My gut says a bard7/sorcerer 7 isn't worth it in the current system, compared to a bard 14 or sorcerer 14. Is it close enough that adding 2 ASIs, 4 spells known, 2 sorcery points, and access to 5th level spells onto a 14th level character make it totally obvious to choose? I feel like it might tip me over, but only just barely.