Personally I work with what we were given and made an simpler factory planet for gel-matrix biopaste.
Three input launchers, each one material.
Okay, I used P2 → P3 on my planet because I got the input materials from P0 → P2 planet setups, but even for a P1 → P3 factory planet it’s easier to just use three launchers and not bother with the additional storage facilities.
But if you do wish to use storage facilities, can you not dedicate a(nother) storage facility to the end product? That too would solve your issue without requiring changes to the game.
While game changes can be asked for, the easiest and in my opinion best solution is usually to work with what you have.
here’s my newest set up, this will probably become the template for my 36x planets factory set up i have 54000m3 of space on the planet and then also i stuuf 35000m3 worth of mats in the poco, mats on planet cook for a bit over 6 days then ill send down the rest from the pocos at some point and send up the GMBP and restart the process this is a very hands off set up as i siad it runs for almost a week after importing and filling up
i crunched the numbers and its FAT isk for about an hours work filling up all planets with mats once a week. this will allow me to focus on more active play instead of spending my time resetting extractors every 24 hours on 36 planets, i can just visit them one a week
eventually ill train up my other 3 alts and run another 18 planets for a total of 54 planets pumping out T3 mats, 6 characters on 3 accounts will plex my 3 accounts and leave me a chunk to reinvest probably will buy skill injectors for my untrained alts to get them up and running pi sooner then later.
looking at a potential +/- 8 bill a month from 36 planets
I do my P3 on different planet from my P2 and again a different planet for P4. Was much easier on the flow and at the end of the day I just wanted to have clean production lines. ps: Im running 90 planets so I needed to make concessions for ease of use. I use 5d cycles and pick up is about once a month with 2 P3 cycles and 4 P4 cycles in there that I do in homesystem.