In general, the market has overtaken hobbyist hacking by a wide margin. Any technique you are considering has already been considered and either adopted or abandoned by the Broadcoms of the world. Basically all radios are now SDR-ish but their firmware only contains a highly-optimized implementation of a single protocol (e.g. 802.11). Sure, a spinal code PHY with a mesh MAC will beat 802.11 by some percentage, but it costs 10x more because it's an FPGA instead of an ASIC so you end up switching back to Atheros/Broadcom radios.