I was under the impression that Senior is mid-level? I thought the ladder went, Junior/Associate, (Just) Software Engineer, Senior (some places have Senior I/II), then Principal, and finally (Optional for really big companies with R&D like Cisco/Juniper/United Technologies), Fellow or Distinguished Engineer (and Senior Fellow).
>a senior engineer at a large company (and thus earn ~$250k in salary)
I'm under the impression that the $250K salary is total comp, usually $150K in Silicon Valley (which is like $80K in fly-over country) and $100K in stock options/bonuses which varies year to year (e.g., what was the annual bonus of SV programmers in the year of 2002-2005? vested options now worth for employees of TWTR and LivingSocial?); also how secure are these Senior Engineer jobs and people's average tenure at those jobs? What is their hourly wage accounting for how many hours they work?
I propose a better formula for salary range for all job ad's, your cost-of-living adjusted annual salary * (1 - % involuntary attrition per year at your company) * (40 hours / avg hours worked of employees in the team) + (50-percentile bonus) + (employee stock options {if not public 0 else 50-percentile of the cohort of the one year price target of stock analysts}).