So I've actually played with Mana Crypt in limited during EMA draft and i'd argue your ramping into more powerful spells then Kaladesh limited.

So if this was Sol Ring versus Chandra I'd pick Sol Ring. It's that close. But I chose to pick Chandra P1P1. I used my own history with Mana Crypt in a non-cube limited format to note that sometimes you don't have the 3 drop, or you do but don't have the 4 drop. I remember in my draft only being able to fast ramp into 4 mana play. then drawing 2 and 3 drops that the mana crypt didn't help with. As a matter of fact 2 of the 3 times I drew it I didn't cast it
Non-Cubed limited games tend to go long. You can die to your Mana Crypt where as you wouldn't to your Sol Ring. I played my 3-1 sealed deck vs his Mana crypt / chandra pool, and he turn 1'd a mana crypt into a Thriving Rhino He didn't have a 4 drop and tapped it once more that game. I found a Revoke Privileges for the Rhino he took 9 damage from his Crypt and I attacked for lethal on 1 combat step.
I also argued that you sometimes draw Mana Crypt on turn 6, where you would love to draw Chandra at turn 6 or any turn really except the last card in the deck. Chandra may be you best draw where Mana Crypt is probably the worse draw. Mana Crypt gives you more powered aggressive starts. but keeps a short life span of being great.

most favored Mana Crypt, our local limited GP HOU top 8 player chose Mana crypt. It was actually his pack that started the question. I suppose his vote counts twice.