I have to disagree with you pity, the drop rate is way worse than that. So far on average, on each of the 12 day event things, I usually have both girls by roughly day 8 (3-4 days per girl, no kobans used). It's almost day 3 of this event, and despite going about 100 runs for Grunt, I have...8 attraction with his girl. 8. not 80. 8. As much as you can say "oh, it's just rng" no, not really. The disparity of any sort of affection shard drop rate is atrociously bad. Add to that this is a Rare quality girl, not a legendary and it's even worse, and more pathetic. Moreso, according to your numbers, I should be roughly halfway through, but 8 is not 50, in fact according to math, no where close.
Honestly the biggest issue with this system is drop rate (I don't mind losing money for shards, tbh it's not that big of a deal). 1-5 on a 100 scale is minuscule and requires a rediculous amount of luck, time, chances, and most probably, koban spending. Doesn't matter if the attraction lasts to the next event if you're only going to average maybe 25 affections shards per event? Basically the new system is going to make either a koban spending spree or you're only increasing your harem through guarantee drop girls.
TL:DR - The suggestion
1) Increase the chance of getting shard drops
2) Increase number of shard drop minimum based on the quality of the girl, ie: starting = 15-25, rare = 10-15, epic 5-10, legandary 1-5, or something along those lines. This further supports the rarity of girls: it's harder to get the higher quality ones.
As it currently stands, it takes longer to get girls now, or you have to pray to extreme luck to not get f**ked out constantly by running and hoping in your 20+ runs you don't get only 1 set of shards, which is most likely going to be a 1.