so are you leaning towards a b-52 style aircraft or a b-1 style aircraft? personally, the b-1 style offers more perforamnce. speed is more important to the attack role, although its useless for evasion. stealth is a must have.
the solution: a tu-22 force purchased from russia, custom tailored to the plans and plaafs needs. new attack and targeting systems, newer weapon carrying abilites, upgraded avionics and navigation, and composite construction for rcs reduction. a coat of ram can be applied. the tu-22 clearly doesnt have much of a future with the russian af, so why not with china? the refuel probe can be deleted, as its not needed. it also males some more distant neighbors feel safe.
the reason for this is that an indegedous programm may take too long. pioneering swing-wing technology and the engienes should take years.