Yamu said:
It's worth noting that the circumstances under which a dipped human becomes an "FEV ghoul" aren't exactly clear. Harold was a vault dweller, but from the sound of things he had been doing the caravan circuit for some time when he went on his expedition to the military base, and this was at a time when the wastes would have been far more contaminated with the NBC leavings of the war than at the start of the first game. On the other hand, Talius had presumably left Vault 13 fairly recently, considering the urgency of the mission, and probably hadn't had much time to accrue any genetic damage.
Not to mention that Richard Moreau was ALSO a vault dweller whose exploits in the wastelands were, not unlike the Vault Dweller's, rather brief, so he should have been relatively "pure" as well. Of course, this is many decades before FO1's story begins, so the pervasive radiation would have been stronger, but it had also subsided enough to allow for civilization to eke out a new beginning by this time. The Hub was well established by the time Harold and the now-called Richard Grey set out to find the source of the mutants, and Grey was turned into The Master. His metamorphosis was the culmination of MANY factors, both the low rad count in his body, the time spent in the vats (he was floating in them for a full MONTH), and sheer spontaneous luck, not unlike the Lieutenant drawing the long straw and turning into an enlightened Super Mutant instead of a stupid one.
If you were to allow for the game to be continued even if you get dipped, that sounds like a massive endeavor. For one thing, you have to face the fact that your journey should NOT be the same as a mutant, because the people of the wastes were not receptive to them, at this point. It was many decades before places like Broken Hills were established that showed any form of open acceptance for non-pure humans, and the Necropolis was a refuge for those kinds of ostracized people. But as far as gameplay is concerned, the actual transformation, I imagine, should have a small basis on Luck. Just like the RP's EPA sex change has a chance to instantly kill the player, there should be a chance that the Vault Dweller getting dipped resulted in catastrophic, fatal failure, as well as the possibility that, like Talius, he/she became transformed into a Ghoul-like Mutant, instead of a Super Mutant.
But that option should really be taken with a heavy, heavy grain of salt, Sduibek. Remember, unlike what I believe you're trying to attain by "reimplementing" certain features into your mod, getting dipped would HEAVILY break the established canon of the game. No matter what could happen to the Vault Dweller, he/she would be rendered sterile, and canonically he/she went on to have children.