Science progression

[KiwiHawk]

Purple, pink, and yellow science all require yellow lab. So rather than being unlocked one after the other, they all become available at the same time. Especially because yellow labs are closely tied to yellow science (the most advanced of the three).

I suggest adding a new lab tier between blue and yellow. This lab would accept purple science and pink science (if enabled).

In vanilla Factorio, the devs deliberately restructured the tech tree so you could choose which tech path to follow first - purple or yellow. In Angel's however, yellow science on it's own without pink or purple unlocks very few techs (Advanced Chemistry 4, Military 4, Power Armour MK 2). Because of this, it feels like Yellow Science is a higher tier than Purple.

[KiwiHawk]

Alternative (much simpler) fix: allow purple science in the blue lab.

Prerequisites make more sense this way as Purple Science takes red circuits. Pink and Yellow Science take blue circuits.

[mexmer]

for now i will allow purple (productivity) as well as purple(advanced logistics from bob) in T3 lab, later i will add T4 lab, and this two will be t4 while utility will be t5