Spoiler:
I think Yusaku should definitely be involved in this arc/series simply because it will be suspicious for him not to be. The Black Org. thinks Shinichi Kudo is dead, so they would assume that his family would get involved at some point to figure out why and who did it. If Yusaku doesn't get involved then that would raise suspicion on Shinichi's 'death' and lead to discovering that he didn't die.
Thus this arc/series, if Yusaku gets involved, will dissolve any possible suspicion that the Black Org. has about Shinichi's death as well as lead to Bourbon being dealt with and possibly captured. If Conan's plan includes a twist that involves Akai showing himself as another person disguised (even if it is the real Akai disguised as someone else disguised as him), then Akai being alive can also be kept secret from the Black Org.
Thus this arc/series, if Yusaku gets involved, will dissolve any possible suspicion that the Black Org. has about Shinichi's death as well as lead to Bourbon being dealt with and possibly captured. If Conan's plan includes a twist that involves Akai showing himself as another person disguised (even if it is the real Akai disguised as someone else disguised as him), then Akai being alive can also be kept secret from the Black Org.