You're alone in the whole wide world thinking that, hahaha.
Really, she gets Mediarahan, a severe Nuclear attack (tho it's such a colossal waste of her SP), the biggest SP pool even beyond characters like Ann and Morgana, Marakujaja, a curing spell for the most devastating status effect in this game, an all around stat so she can do whatever you assign her to be, plus her ultimate weapons dwarf all characters, even the MC.
It's cheating just how much of a boon having her in your main party is compared to any other character, hahaha.
I wouldn't go that far. Her +10 weapon is frankly, completely unnecessary. Definitely not worth fusing the level 87 Persona needed to obtain (i'd argue that Ryuji and Ann have better fusion weapons that are actually viable in the midgame). Makoto's a bit of a late bloomer, because she doesn't carry when you first get her. She needs to wait until level 41 for Mediarama and 48 for Marukkaja, which is a decent portion of the game. When she reaches that point, she becomes the go-to for support.