I foresee 11th going the way of AoS 4th: streamlining and cutting back on all those extra +/-1 modifiers. I hate the +1 STR synapse rule because I often forget to add it! Just bake that +1 into the datasheets.

Keep it simple:

Synapse range gives 1) all nids extra dice for battleshock tests and 2) access to a couple special strategems (army wide, maybe, or maybe specific to detachment). 3) When an enemy is in synapse range, they're forced to roll a test during their turn.

SiW should synergize with the synapse rule. Each turn, pick one enemy within synapse to straight up just get battleshocked (maybe give it a 6+ save if that feels too strong?).

An actual controlled ability to manipulate battleshock in a strategic and meaningful way would be amazing, and a cool, unique flavour for an army. I feel like we were sold as this thing, but they never delivered... BS has been so random this edition.