Hello , having fun time with your mods , but biter eggs are just miserable , as they have no way of upstream upcycle them , other then dumb upcyling of overgrowth soil - is this the intended way ?

Having no easy egg upcycle solution was intended to preserve the challenge of the early promethium packs - the 30mn limit makes ship design more interesting in my mind.
The other use case for quality eggs should be high quality biolabs, but with normal eggs it should still be OK to get rare biolabs with legendary qual modules.
I assumed rare labs should be good enough, and epic/legendary kind of chase items not needed in a "normal" playthrough. Thats also why the mod removes eggs as an ingredient of prod modules.

In very late game with Space Age Overhaul (the intended parent mod), the new promethium loop unlocks a way to upcycle eggs and finally get those legendary biolabs. I even had in mind a "This took some work" achievement for getting 100 legendary biolabs at some point :-). Might still do it in a future update !

tbh i wanted legendery biter eggs jsut for the biolabs , so i guess i would jsut dumb upcycle the soil , that recepie for me is mroe then a headeache then it worth it . I had jsut beaten your overhaul and had much fun , espetialy how stone is much more important in overall production , limtis to space logistics and with most suraface restirctions removed i now have construction hubs on each planet - bit thinking on how to make same hubs but for legendery materials . Still thinking on how to desgin ship that can reach much more potpent promethium asteroid belts in tiem , as i jsut use standart asteroid hauler (200km fast) to get some promethium science while i am figuring out legendery materials for the ship .

Also question on promethium , what's the point of advanced prmethium science if it has the same output as normal , but requires much more complicated input and crafts 6 times longer on top of that ?

It is about 10x less promethium intensive when accounting for prod modules, and you are no longer bound by the 30mn time limit.

As asteroid simulation is a big UPS hog it makes promethium much more megabase friendly. The production loop is significantly harder, but if you want to manufacture millions of promethium packs this is the way :-)

If to ask how it work in concpet , is esentialy you load biter eggs on Nauvis , fly to SP , collect promethium chunks and process them to either upcycle eggs or make science until eggs are spent , then ou fly back to Aquilo from processors and Gleba for bioflux for neutrients (i know you can make it from biter eggs , but then you need same eggs for science) , somehow like that ?

Just trying to wrap my head around on how to approach this , just my usual promethium ship can process 5k biter eggs in time limit (also was able to make speed demon 1 with it, maybe can speed demon 2 if to strip away cargo bay and science production)

As usual, you can do it any way you want, but if you look at the biter egg loop recipe with the 50% biolab bonus you'll see you actually output more than you have to get in, eg infinite eggs as long as you can sustain the loop.
My solution is to have a ~800T ship load something like 5000 quantum processors on aquilo, collect some eggs on nauvis and gleba, then head to the shattered planet. As long as i collect enough promethium, I can loop biters eggs which also provide the nutrients to loop pentapod eggs. I maintain them as long as necessary to get a full shipload of promethium packs, something like 150k per trip before heading back to nauvis.