If there was no limit to anything then there would be no point in the game.
It could be done but I would not do it, if there is no challenge, it is not a game.
You misunderstood, although my phrasing was completely wrong now that I looked at it twice.
I meant raising the limit a bit - modifying its maximum/minimum values through stats/skills/items. Not making it "unlimited" per se, just more flexible.
Example: girls with huge tits traits could potentially gain up to 120 titfuck, while the ones with small tits something like 80 maximum.
I'm asking if it's possible to add a different +/- value modifier to the traits that would affect the limit of the stat/skill, not the active amount.
And I'm only talking about small amounts of modification, 10,20,30 per trait. They could stack though.
So instead of all girls having potentially from 0-100 in any skill/stat, their maximum/minimum amounts would vary depending on their personality/traits and items - with values like 20-120, 40-100, 0-60 etc.
If anything, this serves as a technique increasing difficulty - because most of the traits would offer positive effects only at the price of very detrimental ones.
The reason why I touched upon the subject is partially due to my thought about a "Flat Chest" kind of trait... logically enough, a girl with nothing there shouldn't be able to even perform titfucking at all - what's she gonna do, rub her nipples all over? Yet, at the moment, it's possible for ANY girl to be an absolute prodigy at any sex act. How so? All things in life require a certain amount of talent- some people were simply born doing certain things better than others.
I also like the idea of certain girls being "specialised" in certain matters - one of your girls is good at that, the other at something else, and so forth.
It would most certainly add variety to the game, and again, perhaps even balance - since you can't just have every girl with maxed skills in everything after enough grind.