Even with (a) it's tough. If you're employee 1-13 you're getting maybe 10-20bps. At a unicorn valuation that is $1-$2m before you take into account dilution, liquidation preferences, taxes, etc etc etc.
(I, in my infinite wisdom, traded it down to 25 bps for 15 k$/yr more in salary. Whoops)
Can you narrow 1000 companies down to 20 that have a better than average chance of success? Sure you can! And you should, and you shouldn’t treat the options as worthless.
All it would take i think is for companies to start offering larger stakes to employees, with the other two factors remaining the same, and the math might make it worthwhile. But they won’t do it.