[As System explained Host, System only has one task, to increase Host's Chakra without limit, however increases in physical and spiritual energy of Host, which results in the physical and spiritual state of Host's body traits somewhat similar to Ōtsutsuki's...]
[And Increase in ocular power of Host's Sharingan, eliminating blindness, access to abilities, and compatibility are all inevitable, passive outcomes and results, which will happen even with and without System's involvement.]
"Well, if you say so," muttered Kakashi, and then asked, "Though it's not hard to believe that an increase in my chakra reserves makes such gains, however you didn't answer properly, if Sharingan becomes compatible with me, then would I gain access to Susano'o?"
[Negative. System cannot accurately answer it, because it's not a direct passive outcome from System's boom of Chakra growth without limit.]
[However Susano'o is an obvious ability of any Mangekyō, so even without a complete pair, Host might or might not gain access to it.]
Kakashi nodded, and stayed silent for a moment, thinking if there's anything he can ask the system now, since he wouldn't have this chance for who knows how long.
After a few moments he asked, "Hey, there's one more thing I wanna ask, would my Sharingan... can evolve to Rinnegan with my chakra reserves increased to and even higher than Ten-Tail's reserves level in future, which can match requirements for Yang and Yin Release Chakra for a Sharingan to evolve in Rinnegan?"
[Negative. Rinnegan is Dōjutsu of Hagoromo Ōtsutsuki, Sage of Six Paths, and to evolve Host's Sharingan in Rinnegan, Host needs Potent Yang Release Chakra of Ashura and Potent Yin Release Chakra of Indra's.]
[Even though the Chakra, every Shinobi has is derived from Hagoromo from one point, and Host can match and even grow the quantity of his Chakra higher than Hagoromo in future, but matching that high quality required for Rinnegan is still out of the question.]
Kakashi sighed in defeat, though he didn't have his expectations high, but still, he wished for his Sharingan to evolve in Rinnegan if possible. He asked, "So, you are saying that quantity of my chakra and later Yang and Yin Release Chakra can't substitute the quality of Ashura's Yang and Indra's Yin Release Chakra, which is needed for a Sharingan to evolve in Rinnegan?"
[Affirmation. Ashura and Indra are inherently have Ōtsutsuki's Bloodline, so their Chakra itself is highly potent than any normal Chakra any Shinobi can have, therefore even quantity alone, simply can't substitute the higher quality.]
Kakashi sighed again, looked outside of the window, at the mid-night moonlight, thought a bit, while mumbling, "Potency? Hmm.. Is there any way to make Chakra Potent normally, otherwise, I might require Hashirama's cells transplantation, which is risky, and I definitely don't want to go to Orochimaru for that ever, If I choose that path!"
"Even Tsunade has also done her grandfather's cells transplantion, but she can't exactly be said to be a good choice for Hashirama's cells transplantation in others, I only remember her doing that for Naruto, for his lost arm, but Naruto himself was Ashura's reincarnation."
It would be sounds stupid to think that Naruto, current Reincarnation of Ashura, died after becoming a tree from the cell transplantation of a previous generation of Ashura's reincarnation.
Thus, Kakashi thinks that it wasn't alone that Tsunade was good at purifying Hashirama's alive and full of vitality cells for transplanting them in others safely, but the person she done it on was Naruto, so chances even without purification of Hashirama's cells would be a success for Naruto, as they wouldn't reject his body violently and consumes him.
[Does Host have any other queries?]
Seeing the System continuously asking him the same question whenever Kakashi stopped speaking for a moment, Kakashi felt little irritated, dryly sighed and asked, "Hmm.. Can't you just wait for a moment, why are you in a hurry to leave, do you have to go meet your girlfriend or something?"
[.....]
Then Kakashi once again started to muse, "Hashirama's cells transplantation is a risky thing, in my opinion anyone other than Ashura and Indra's reincarnations, no one can survive easily. Though integration still takes time. Even Obito only survives thanks to Madara, who was there to his aid, and replacing his right crushed side with substance of Gedo Mazo, the White Zetsu."
"And Yamato was a special, one in a billion or even trillions, single case, whose genetics somehow tolerates and matches Hashirama's cells without getting destroyed, plus Orochimaru in experiment on those 60 kids, has only used small amount of cells for Wood Release alone and nothing much."
"Aside from these people, only three remains, Orochimaru, Kabuto and Danzō. However, none of them has transplanted Hashirama's cells directly, Orochimaru can used his consciousness transfer Jutsu, to protect himself from being consumed. Kabuto absorbed DNA of several powerful Shinobi's, including Orochimaru. And Danzō, he only has separate arm, full of Hashirama's cells."
"Though the true master of them is always going to be Hashirama Senju himself, however Ashura and Indra's reincarnations are more compatible than any others, as with Indra's Chakra, it produces Six Paths Chakra and with Ashura's, it's about familiarity. And special case like Yamato, are very very rare, and I am definitely not comes in that category."
Thinking all this, Kakashi nodded to himself, and concluded, "Considering this, I shouldn't take such a risk, and even without Rinnegan, I would be very strong. However, if I can, I would really want to give it a try, and there definitely should be a way for increasing the potency of Chakra naturally without major risks!"
He closed his eyes, right hand on his chin, thinking deeply, and he finally remembered, "Oh... How can I forget Sennin Mode! Senjutsu Chakra, Sage Mode is said to make Chakra more potent than normal when used. Yeah, Hey System, if I learned and master Sage Mode in the future, would that can make my Chakra slowly Potent enough for Rinnegan evolution?"
After asking, Kakashi curiously and with anticipation looked at his front, on the transparent screen.
[Probably can or can't!]
Kakashi looked at the system in a deadpan look, and asked, "Hey, what's with this half-baked answer, probably can or can't? Give me a proper response at least."
[Anything indirect result of system's power, of increasing Host's chakra reserves without limits, are the only things that system can be sure of..]
[However anything that would make changes for Host aside from the direct impact of Chakra Reserves Growth, system can't answer that accurately.]