Oh you are already at the point of no return lol and it is working out nicely!
You will be happy brother but do plan on more seeds than you remember back in the day with dirt weed with seeds in it. I found my buds have WAY more seeds in them when i let them fully pollinate which is not a bad thing i just feel bad when i hear my grinder crushing 30% of the seeds but screw it haha many many uncrushed seeds fall below in the grinder so no worries. i started out hand picking the seeds out of the buds but it gets time consuming fast, just grind them lol
I just finished a solo cup grow where i dusted the preflower pistils with red poison pollen and it worked out great! the lower part of the buds had some seeds and the top buds have very few to none. so i would say if you collect pollen and you dust future plants with it 1 time you will get some cool seed crosses without getting pounded with more seeds than we want.
But try things your own way, that is how i learn