Just counted: I need 35 lvl 20 Red Bloom Dragons to evolve the remainder of my slice girls (most are lvl 40-60 already). So I'll be doing that 50 stam map a lot today. Probably going to do the same tomorrow for blue dragons..
lvl 100 dragons are less of an issue, since they're often rewarded during events. And on the lvl 50 maps, I'll occasionally get them as undesirable side-catch anyway..