68EC020: 32-bit data bus. Address bus is 24-bit.
68020+: 32-bit data and address bus.
68000/68010: 16-bit data bus, 32-bit CPU internal data bus (or more like 2x16 but this is only implementation detail
). 24-bit address bus.
Custom chip "bus": OCS/ECS 16-bit data. AGA 16, 32 or 2x32 (two fetches per memory cycle). Only bitplane and sprite DMA can use wider bus.
Chip RAM bus width: 16-bit in OCS/ECS. A3000 has special circuitry to allow 32-bit CPU access. 32-bit in AGA.
Make your choice