Without having a look at exactly what is being done, it is hard to tell.
BUT, looking at it on the surface, yes, it is too expensive.
"I understand that $750 for an agency may not be worthwhile, however I will also be paying them $6,600 to re-write and keyword optimize 58 URLs, so there is more involved than only $750. Furthermore I will probably engage them for a content marketing campaign to the tune of $2,500 per month."
Setting up goals in Google analytics should not be a $750 cost all by itself. This can be acheived in about 30-60 minutes. I think you are being charged for analyzing the data, (which usually doesn't take a real long time) rather than the actual setup. This is normally absorbed into the cost of doing the SEO. Again, I'm not familiar with everything they are doing for you, but for the same job, (seo, analytics, content marketing) we would charge much less. I would like to see their proposal, to see if you are getting taken advantage of.
Spencer said it best when he stated "They easily could be trying to overcharge you if they think you can afford it." I have been involved in the industry for 12 years, worked at a few agencies before I owned my own, and this happens a lot more than you think. Seeing people get taken advantage of was one of the driving factors for me to set up my own company, and hire my own team. Just couldn't watch it anymore.