@Sage Chow
Alright I had to read through that carefully and think carefully about how that challenge interacts with the ones I've already been given. I think you missed the bit about being only able to catch one Pokemon of each primary type, which makes the final stipulation impossible (which I won't be doing anyway because the Johto Safari Zone works MUCH differently than other Safari zones and would take weeks to complete).
I think the way this'll work is that the Safari Pokemon ignore all previous Pokemon obtaining and usage restrictions (Basically, just Articblast's and Demo gorgon's challenges). However I can only ever have one of them in use at a time (switching only after each gym), to prevent me from flooding my team with restriction-less Pokemon (not that I would but anyway). The exception for this is for the battle with Blue, and any grinding time required to prepare them for Blue.
At first I thought you were having me slowly replace my team 1 Pokemon at a time but rereading it made me realize that's not what you meant XD and that's good because otherwise it'd conflict with my team building restrictions too much. As such, I will accept your terrifically crafted challenge!
@Human Destroyer
You are challenged to choose a Pokemon you actually use in battle to box after every gym, and replace that Pokemon with a Pokemon from one of the routes adjoining the city of the gym you just beat. The boxed Pokemon cannot be used for anything other than HMs for the rest of the game, and cannot be some random piece of shit you catch just to box. It must be a Pokemon you actually USED.
Yes this is somewhat inspired by Sage Chow's challenge, I couldn't resist since it was such a good idea.