Yeah, mainhand + offhand attack is completely trivial unless shadowblade or Tenser's transformation is in play, then they can both be rather significant. > let me do the math
I think adding in the rider is pretty unfair, my DM has never given me a booming blade proc. in my life. And another thing is that you're doing that's skewering the calculations--assuming two enemies right next by each other. I already agreed twin sorc. is better for multiple targets, though. With twinned you can literally double DPS.
Spirit Guardians is 3d8 AOE, but is halved pretty often early, esp. if you focus on dex/con. Spiritual Weapons uses your bonus action. Twinned Booming Blade is 1d8 + 1d4 + 3 to TWO targets if they happen to be next by each other. If you quicken to use booming blade twice, then you don't get the spiritual weapon add.
If it were single target and you used spirit guardians + spirit weapons instead of shadowblade + quicken, you'd be much less damage.
5d8 + 1d4 + 6 for around 31 DPR if 100% accuracy and the save was failed.
If you used quicken + 3rd slot shadowblade, you'd be getting 8d8 + 6 for 42 DPR.
A level 6 bladesinger does 7d8 + 1d6 + 6 for 40.5 on single target, as you've said, which is pretty close to the Sorc's single target. >buffed bladesinger with the old shadow blade interaction
True, SB no longer works with BB. Hence why bladesingers moved to summon fey, animate objects, and tenser's transformation. >forgoing warcaster
I think most bladesinger builds do, you have a high enough percentage of making the 10 DC con save early game, so you just grab resilient (CON) and ignore warcaster. >Bladesingers need their int a lot more than you need your charisma
True. Bladesingers are also more focused on being a wizard, too. At higher levels, you're essentially a wizard that can get high AC + Con saves and can smack things with a sword once in a while. Makes the early game less boring, though.