I have only 5 girls not currently at 100% affection and 4 of those need toys, i've not had a gem girl for so long I had 200+ 2% gems saved up and another 100+ books and cakes not to mention Nuzuna cakes so for me it was worth forging a few gifts to get Hanamomo's stats up some more (1st ever 6* and 1st Waifu so of course 1st to get 2nd affection).
But as others have said, it's not really worth doing for newer players except for one thing: 2nd Affection Unlock Flowers, they sell 6 in the LC shop and 2 are going for only 150 each. Those I would recommend getting and either using to unlock 2nd affection for your 100% girls or stocking up till gifts are easy to come by just because of how cheap they are and the fact that the only other thing in the LC shop worth having is the 6* skillbloom.
Flower Knight Girl: 255445855