You shouldn't think about balance based on what makes the most sense (compared to real life sports), but what is most balanced for this sport game, think outside real world rulesets and limitations.
There is a fine balance line between killing being tactically important and useful, but better killing not being 100% a guarantee of victory. If you added more respawn time, or sent dead players to sidelines, it would make killing a lot more important than ball moving since a dead player is removed from play longer, making it much easier to move ball. If respawn timer is lowered, or dead players get a more favourable respawn, then ball maneuvering skill becomes more important.
Ideally a team with better passing and ball moving abilities should be equally competitive with a team that's better at killing the final result determined by onfield clutch actions, like all sports. Both would have strengths and weaknesses. All balance tinkering should be analysed with this ideal in mind, and if currently one strategy is stronger than the other (tho there should probably always be some bias preference towards ball movement, since that's the signature gamemode of the zone that distinguishes it from say Battle mode which is pure killing).
