Have Crit Damage scale with Critical Strike Chance

I'm sure this has been brought up before and I'm sure there's a reason it hasn't been implemented but would that reason be? I can see the power curve being too exponential but I personally think the point of a lategame hypercarry is to have a generally neutral or weak early game that leads into it rather than what we've been seeing with strong early game ADCs becoming hypercarry lategame ADCs.

For example, have all champions start with 150% Crit Damage and have each Critical Strike Chance item grant additive % based on approximately half of its Crit Chance value (so at 100% it levels out to 200%).

Numbers can vary but the concept is what matters (ofcourse with basic early game buffs to the other stats and effects on Crit items since Crit itself will be altogether even weaker in the early game).