1: Pandora explicitly states that most Seers would not be able to accomplish what Tedd has accomplished if in the same position, indicating that regardless of power he's at least a prodigiously skilled seer.
2: Nothing that's been told to use about seers explains why Tedd glows when he feels loved.
1. Skill and power are entirely different things. If I had been given all the same advantages as Elton John, I guarantee you that I would not have become a famous musician. That doesn't mean he's more powerful than me. Pandora was complimenting Tedd's cleverness and ingenuity, nothing more
2. So? A mystery existing doesn't automatically confirm your personal headcanon. That's the height of wishful thinking.