Should I Consider Heavy Blade on +atk B!Lucina?

I mainly use her on a team with Delthea so she'd regularly get +6 atk, thus raising Lucina's atk stat to 59. Obviously I'd use the aether she comes with as the special. It's an unusual build which is why I'm asking for a second opinion, but I have the means to make it happen.

side note: If I were a whale with the feathers to spare, I'd kinda want to put Galeforce on her with HB because she's also on a team with B!Roy. Delthea to give that 6+ atk, a dancer, and two HB Galeforce units sounds like the best kind of nightmare team.