It wouldn't necessarily be too unbalanced. Rather, it depends on how it's implemented. Perhaps the auto-healing of Better Future blocks would be very slow and still require battery power?
That said, it may be more balanced if Better Future still required a Repair block, like all the other techs.
Perhaps, instead of repairing all blocks in a sphere, it repairs all blocks within a cube? Or, perhaps it repairs [x] number of blocks away from the Repair block, regardless of radius or cube size? Another possibility: Maybe it could repair all blocks on the entire vehicle, but the power required would be large and scale with vehicle size and/or it would fail to repair blocks from other corps?
Hey, I've moved the three posts above, from here, to their own thread. Also added this title. I think it's worth giving each idea it's own thread, to give space to explore the idea fully and for full visibility.