Generally speaking:
Any component substitution of the same size, value, type and tolerance should be fine.
You could buy 0.1% 50k resistors instead of matching 1%ers.
I haven’t tested another op amp, so can only speak for TL072, but this is for the octal boards where nothing really matters much (LED drivers only).
TL4050 should be fine? The accuracy is anyway a bit overkill for an input stage like TL074
Check the mounting heights of pinheaders are enough for the corresponding sockets.
Molex headers are not really needed here.
