It's certainly more cinematic that way.It should matter whether my Wizard character casts a spell well or not, just like it matters whether a Fighter character swings a sword well or not.
Saving throws are a weird wargame thing that don't really make a lot of sense for a lot of spells. In games where you don't have them, and it's down to the caster's roll (including 4E), that leads to honestly better/more interesting roleplaying and just a better, more engaged way of thinking about spellcasting.
D&D could particularly use that, because the fire-and-forget, slot-based system D&D uses (admittedly Concentration means some stuff is no longer fire-and-forget!), is easily the least player-engaged form of spellcasting I've come across in a TT RPG.