Chicago is a real city with skyscrapers and trains and everything. Any experience you want - whether white-picket-fence suburbia, downtown glass-and-steel high rise, or trendy urban neighborhood with street life - is available at within a reasonable housing and commute time budget. The tech opportunities there are concentrated in Office Space-type cost center IT on one hand, and commodities trading on the other, so an engineering-first company would be highly attractive. You might get some domain-specific talent re: radios from the ghost of Motorola.

Chicago belongs in the same breath as NY/SF/LA, so wouldn't be seen as a huge step down for someone relocating, but is drastically cheaper.