I'm going to have to disagree with that.
You can actively dislike someone who is charismatic. Maybe you dislike their political positions. Maybe you just don't want to listen to what they say. Maybe you know that they're actually a horrible person, but since no one can prove they were behind all those murders but you know they were... Charm is more powerful than just having a high Charisma.
Top give an example, Xykon (the lich) is quite charismatic. (He's the leader of a fairly large evil horde, after all.) Roy has reasons to hate him.
If Xykon successfully charms Roy, then Xykon is Roy's best friend for 1 hour/level (barring some kind of countering magic). There is no charismatic person in the world who could do that sort of thing. A charismatic person can only indirectly influence someone's emotions, unlike a spell.
(It's so hard to give good examples, as we're not allowed to talk about politics.)
Well, the spell description obviously implies the target is still able to disagree, if they make their check instead of you. You can disagree if you want, its the right of being a DM, but you may want to consider that this spell does not turn the targets mind into a puppet on strings, it just makes them view the caster in the most favorable light possible. It is far from total control.
Don't let the mechanics (the dice rolls) hide that fact. They get the rolls because they can still disagree. You can use the dice roll mechanic, or ignore it because you wrote up the NPC and know enough of their goals and beliefs to say they would not do such actions, without a dice roll.
So if you want to make a first level spell defacto as powerful as a dominate spell, its the individual DM's perogative to do so. However I look at it as strongly influencing, not irresistably forcing the target. Which keeps me from having the issues the previous posters have mentioned.
I also take the time to decide on major, or important, NPC's religion, basic beliefs, alignment, etc... just in case they are charmed. IF nothing else I can give a bonus to any save that goes against what I determined their personality, belief's, morals, goals, etc... to be. Its my job as DM to do so when justified, and it keeps Charm Person a first level spell in effect as well as in how its labeled.