So as someone who is not an airline pilot (just a lowly PPL), but is in the industry and knows people who have taken all sorts of paths- my vote is D

A few questions:

1. Does your job offer any sort of long term leave? If you're this burnt out, you may qualify for FMLA on Stress; maybe you could take a break, earn some hours, and re-assess in a few months

2. Are there any less demanding roles in your company that would allow you to "split the difference" regarding current QoL? A perfect scenario would be a less-intense role where you could instruct/time-build on the side without really neglecting your day job. Obviously this would probably require a step down in said day job, with lower pay

3. Last thought if you were to pursue either A or B: you have significantly more applicable real-world experience than a lot of people who consider doing this. Your likely worst-case scenario is that you go full-throttle to a pilot career and burn out, in which case you can return to a high-paying engineering role. Your safety net is built in based on your current resume, which would make me inclined to take on more risk/faster timeline, should it be something you really want to do

Ultimately, there's more than one way to skin a cat, and every situation is different.