1)
Why did he say "Ahavti Me'on Beisecha"?
1.
Radak: I hate the congregation of evildoers, but I love the house in which the Aron was 1 . Leviyim, Kohanim, Nevi'im, Chasidim and Kadosh servants of Hashem, like Asaf and his brothers, were there.
2.
Malbim: I do not come to the Mikdash amidst habit, rather, because I love Your house, for Your honor dwells there.
1
This was before the Mikdash was built. (PF)
2)
What is "Mekom Mishkan Kevodecha"?
1.
Radak: The place where the Aron was, there honor dwelled on Nevi'im and people of Ru'ach ha'Kodesh.