Great process and thank you for documenting so much of your work! I am actually very surprised that it won't idle without throwing a code from maxing the fuel trims. Some OBD-II readers can show values above 30% so it may be beyond the maximum allowed amount. I wonder if the fuel at idle is not only controlled by the MAF but also the IAC? The throttle plate is normally only about 11% open at idle and once you start to accelerate, even slowly, it's higher around 17% and will need more fuel flowing. If you had a piggyback controller you could easily bump up fuel between 500-1000 RPM by 15-20% and it would be an easy solution.

If you do decide to replace hoses, also look at the EVAP hoses. The ethanol fumes cause these old hoses to crack faster than the rubber supply and return lines in the engine. The fuel line hoses are very stout and will probably be fine.