Nightmaher's background as a "collab" girl more or less had something to do with that. More than some of her abilities, her stats in particular took a blow; hence my grade on them. As a friend on the wiki wrote on her page, Maher was introduced as a giveaway from a specific 5000pt gacha promo such that she was relatively easy to obtain outright (this was way back when exchange ticket promos were rather infrequent and rainbow medals were far from a concept) compared to most rainbows that were introduced normally.
That said, I might have gone a little, er, harsh with my assessment of Nightmaher partly because I already got Saffron, but at the time, I was focused on a "hard" counter setup, as Ghostmon also has Saffron. Nevertheless, Maher is still considerably flexible to enough to work with (e.g. in a mixed counter lineup). Now that she's buffed in terms of abilities (notably counter damage) and stats (I thought my eyes were playing tricks on me; I swear her defense was around 2.7k, now it's up to 3k), I might give her a second look this time.
Anyway, we're good, mofu.
Moving on, I have to note that some recently mentioned girls in this thread have been buffed: Nightmaher, Habranthus, Apricot, and Apple (Tanabata). What timing.